What Is a Negative Inotrope?

It belongs to class III antiarrhythmic drugs. Mildly non-competitive alpha and beta adrenergic blockers. And has mild class I and IV antiarrhythmic drugs. The main electrophysiological effect is to prolong the action potential and effective refractory period of each myocardial tissue, which is beneficial to eliminate reentry excitement. Inhibits fast sodium ion inflow from the atrial and myocardial conductive fibers and slows the conduction rate. Reduce the sinus node self-discipline. It has no effect on resting membrane potential and action potential height. Atrioventricular bypass inhibits forward conduction more than reverse. Due to the prolonged repolarization, the QT interval of the ECG was prolonged and the T wave changed. Intravenous injections have mild negative muscle strength but usually do not inhibit left ventricular function. Direct expansion of coronary arteries and surrounding blood vessels. Can affect thyroid hormone metabolism.

It belongs to class III antiarrhythmic drugs. Mildly non-competitive alpha and beta adrenergic blockers. And has mild class I and IV antiarrhythmic drugs. The main electrophysiological effect is to prolong the action potential and effective refractory period of each myocardial tissue, which is beneficial to eliminate reentry excitement. Inhibits fast sodium ion inflow from the atrial and myocardial conductive fibers and slows the conduction rate. Reduce the sinus node self-discipline. It has no effect on resting membrane potential and action potential height. Atrioventricular bypass inhibits forward conduction more than reverse. Due to the prolonged repolarization, the QT interval of the ECG was prolonged and the T wave changed. Intravenous injections have mild negative muscle strength but usually do not inhibit left ventricular function. Direct expansion of coronary arteries and surrounding blood vessels. Can affect thyroid hormone metabolism.
Chinese name
Amiodarone
English name
Amiodarone
nickname
Andodalon, Oralone, Amiodarone, Eamiodarone, Acetolone
Chemical formula
C25H30ClI2NO3
Molecular weight
681.7725
CAS Registry Number
1951-25-3
EINECS registration number
217-772-1

Introduction to Amiodarone Compounds

Amiodarone Basic Information

Chinese name: Amiodarone
Chinese alias: ethiodon; humperidone; amiodarone; amiodarone; amiodarone; kadaron
English name: amiodarone
English alias: (2-Butylbenzofuran-3-yl) (4- (2- (diethylamino) ethoxy) -3,5-diiodophenyl) methanone; Tranquerone; AMidorone; (2- {4-[(2-butyl-1- benzofuran-3-yl) carbonyl] -2,6-diiodophenoxy} ethyl) diethylamine; Atlansil; Amiodarone; Cordarone; Atlansil
CAS number: 1951-25-3
Iamidone 2
Molecular formula: C 25 H 29 I 2 NO 3
Molecular weight: 645.31200
Exact mass: 645.02400
PSA: 42.68000
LogP: 6.93620

Amiodarone physicochemical properties

Density: 1.58 g / cm 3
Melting point: 156ºC
Boiling point: 635.1ºC at 760 mmHg
Flash point: 337.9ºC
Stability: stable, incompatible with strong oxidants.
Storage conditions: storeroom ventilated, low temperature and dry
Vapor pressure: 4.95E-16mmHg at 25 ° C

Amiodarone Safety Information

Customs Code: 2932999099
WGK Germany: 3
Danger category code: R20 / 21/22
Safety instructions: S36
RTECS number: OB1361000
Dangerous goods sign: Xn
China Customs Code: 2932999099 [1]

Amiodarone Drug Description

Amiodarone Classification

Circulatory Drugs> Antiarrhythmic Drugs> Extended Action Potential Duration Drugs

Amiodarone dosage form

1. Tablets: 0.1g each; 0.2g;
2. Injection (hydrochloride): 0.15g (3ml).

Amiodarone Pharmacokinetics

Delayed oral absorption. Bioavailability is about 50%. Apparent distribution volume is large, mainly distributed in adipose tissue and fat-rich organs. Followed by heart, kidney, lung, liver and lymph nodes. The lowest are the brain, thyroid, and muscle. In plasma, 62.1% bind to albumin, and 33.5% may bind to beta lipoprotein. Eliminated primarily in the liver. The half-life is 14 to 28 days, a single oral administration of 800 mg is 4.6 hours (ingested in the tissue), and long-term medication is 13 to 30 days. Bleeding drug concentration can still be measured six months after discontinuation. Peak blood concentration was reached 4 to 6 hours after oral administration. Steady-state blood drug concentration can be reached in about 1 month, and the steady-state blood drug concentration is 0.92 to 3.75 g / ml. The effect begins in 4 to 5 days, the maximum effect is reached in 5 to 7 days, and the effect can last for 8 to 10 days after stopping the drug, even for 45 days. It takes effect 5 minutes after intravenous injection, and the withdrawal can last for 20 minutes to 4 hours. The effective blood concentration is 1 2.5g / ml, and the poisoned blood concentration is 1.8 3.7g / ml. Hemodialysis cannot remove this product.
Amiodarone is transported slowly in tissues with high affinity. Its bioavailability varies from person to person, ranging from 30% to 80% (average about 50%). Peak concentration was reached 3 to 7 hours after a single oral dose. Load-dosing usually works after one week (several days to two weeks). Amiodarone has a long half-life and significant individual differences (20 to 1Q0 days). In the first few days of treatment, most drugs accumulate in the tissues, especially adipose tissue, which begin to clear after a few days, and reach a steady state concentration that varies from person to person within a few months.
Due to the above characteristics, a load should be given in order to quickly saturate the tissue and exert a therapeutic effect.
Part of the iodine is removed from the molecule and excreted in the urine. Administering 2O0mg of amiodarone every day can excrete the equivalent of 6mg of iodine, so most of the remaining iodine is excreted by the liver through feces. It is rarely excreted through the kidneys, so patients with renal insufficiency are allowed to use regular doses of amiodarone. It takes several months to remove the drug after stopping the drug. It should be noted that the residual effect of the drug will last from 10 days to January.

Amiodarone pharmacological properties

Antiarrhythmic effect
a. Extend the phase III of the cardiac fiber action potential to reduce potassium influx (Vaughar Williams class III), this effect has nothing to do with heart rate.
b. Reduces sinus node self-discipline, as it can cause bradycardia that does not respond to atropine.
c. Non-competitive - and -adrenergic inhibitory effects.
d. Slows sinus, intraatrial, and nodular conduction (more pronounced with fast heart rate).
e. Does not change indoor conduction.
f. Prolong the refractory period and reduce myocardial excitability in the atria, nodal areas and ventricles.
g. Slow the conduction of the atrioventricular bypass and prolong its refractory period.
Antiangina
a. Reduce peripheral resistance, slow heart rate and therefore oxygen uptake.
b. Antagonistic effects of non-competitive alpha- and beta-adrenergics.
c. Acts directly on myocardial smooth muscle to increase coronary output.
d. Reduce aortic pressure and peripheral resistance and maintain cardiac output.
3 Others have no significant negative muscle effect.

Amiodarone indications

Applicable to atrial premature beat, ventricular premature beat, transient atrial tachycardia, recurrent supraventricular tachycardia, and less effective on persistent atrial fibrillation or flutter than quinidine. Not satisfied with the effect of maintaining sinus rhythm after atrial fibrillation. Intravenous injection is suitable for paroxysmal supraventricular tachycardia, especially for patients with preexcitation syndrome. It is also used in patients with ventricular tachycardia who have not been treated with lidocaine. This product is a broad-spectrum antiarrhythmic drug. The curative effect is significant, but due to its many side effects, it is currently listed as a second-line antiarrhythmic drug.
For severe arrhythmias that are ineffective or inappropriate for other treatments:
1. Atrial arrhythmias (atrial flutter, atrial fibrillation, and maintenance of sinus rhythm after the rhythm);
2. Knot arrhythmia
3 Ventricular arrhythmias (treatment of life-threatening ventricular premature contractions and ventricular tachycardia and prevention of ventricular tachycardia or ventricular fibrillation);
4 Arrhythmia with WPW syndrome
According to its pharmacological characteristics, amiodarone is suitable for the above arrhythmias, especially with organic heart disease (inadequate coronary blood supply and heart failure).

Amiodarone dosage

1. Generally give the load first, 0.2g each time, 3 times a day, after taking 1 week, change to 0.2g each time, 2 times a day, and then take 1 week, and then change to a maintenance amount of 0.2g, once a day. After 3 to 6 months, the effect can be gradually changed to 5-6 times a week or once every other day, 0.2g each time. The load for severe fatal arrhythmias can be increased to 800 mg per day. Those with significant weight may aggravate as appropriate.
2. Intravenous administration: the load is 3 5mg / kg, and it is injected within 5 10min after diluted with 5% 10% glucose solution, and the dosage can be repeated after 0.5 1h. After the effect is achieved, the intravenous drip maintenance amount is generally 0.5 to 2 mg per minute. The dose can be adjusted according to the effect and can be used continuously for 3 to 5 days. Excessive dose can inhibit myocardial contraction.

Amiodarone is contraindicated

(1) Cross-allergic reactions, those who are allergic to iodine may also be allergic to this product.
(2) This product can enter the fetus through the placenta. The original drug and metabolites in the blood of the newborn are 25% of the maternal blood concentration. It is known that iodine can also pass through the placenta, so pregnant women should weigh the advantages and disadvantages when using it.
(3) This product and its metabolites can be secreted from milk. People who take this product should not breastfeed.
(4) The following conditions should be disabled:
Those with abnormal thyroid function or previous history;
Those who are allergic to iodine;
or degree atrioventricular block, double beam branch block (unless a pacemaker is available);
Sick sinus node syndrome.
(5) The following situations should be used with caution:
sinus bradycardia;
Q-T prolongation syndrome;
hypotension;
liver dysfunction;
pulmonary insufficiency;
Severe congestive heart failure;
The heart is significantly enlarged, especially those with cardiomyopathy.
Cataract, arrhythmia, cardiogenic syncope, bradycardia, and atrioventricular block are contraindicated.
Those with abnormal thyroid function, indoor or atrioventricular block, sick sinus syndrome, prolonged QT interval syndrome, and iodine allergies are contraindicated.
Hepatic and renal insufficiency, pregnant women and lactating women should be used with caution.
Caution should be used for patients with suspected potential sinoatrial node lesions with supraventricular tachycardia, otherwise a longer period of sinus arrest may occur.
Significant enlargement of the heart, especially in patients with cardiomyopathy, is relatively contraindicated, because it can lead to cardiogenic shock.
This drug should be disabled in patients with pulmonary insufficiency.
The digestive system shows nausea, vomiting, loss of appetite, bloating, and dry mouth. If taken during or after meals, it can reduce the reaction. Long-term medication, 15% to 40% of asymptomatic liver dysfunction occurs, aminotransferase can be increased 1.5 to 4 times, without stopping the drug, but need to be closely observed.
Hyperthyroidism caused by this drug is more common in areas with low iodine intake, while those with hypothyroidism are more common in areas with high iodine intake.
Occasionally, photophobia, halo, blurred vision, or discomfort can occur. There are also reports of poor color vision, papillary lesions, and papillary edema.
This medicine can also cause iodine rash, dark blue pigmentation (blue skin disease), nodular erythema, ecchymosis, hair loss and psoriasis.

Amiodarone precautions

The onset and elimination of the oral effect of this product are slow. It is not advisable to add excessive doses in the short term in order to obtain curative effects to prevent overdose;
This product has a long half-life, so you should pay attention to the interaction when switching to other antiarrhythmic drugs after discontinuation; because most adverse reactions are related to the course of treatment and dose, those who need to take the drug for a long time should use the minimum effective maintenance amount as much as possible, and should regularly follow Diagnosis
Monitor blood pressure and electrocardiogram, pay special attention to QT interval when taking orally.
Follow-up inspection should be taken during medication.
blood pressure;
ECG;
liver function;
thyroid function, including T3, T4 and thyroid-stimulating hormone;
lung function, lung X-ray film;
Ophthalmology.
During the medication, the ECG should be reviewed frequently. If the QT interval is significantly prolonged (> 0.48s), it should be stopped.
Always pay attention to changes in heart rate, rhythm, and blood pressure, such as discontinuation if the heart rate is less than 60 beats / min.

Amiodarone adverse reactions

Cardiovascular
Compared with other antiarrhythmic drugs, the adverse reactions to cardiovascular disease are
Iodamine 3
less. include
Sinus bradycardia (less than 60 beats per minute), transient sinus arrest, or sinoatrial block, atropine cannot fight this response;
Atrioventricular block;
Occasional polymorphic ventricular tachycardia, accompanied by prolonged QT interval;
Hypotension occurs during intravenous injection. The above conditions should be discontinued and can be treated with booster drugs, isoproterenol, sodium bicarbonate (or sodium lactate) or pacemakers; attention should be paid to correct electrolyte disorders; polymorphic ventricular tachycardia can be used to develop ventricular fibrillation Turn around. Due to the long half-life of this product, adverse reactions to treatment need to last 5 to 10 days. The most common cardiovascular system is prolonged Q-Tc and sinus bradycardia. Can cause or exacerbate arrhythmias; sinus arrest, sinoatrial block, and various conduction blocks; borderline rhythm, ventricular tachycardia, ventricular flutter, ventricular fibrillation, or cardiac arrest; heart failure and cardiogenic Shock and so on. These reactions can be exacerbated by hypokalemia. It is generally believed that the incidence of cardiovascular fatal reactions is higher in intravenous administration than in oral administration. Thrombophlebitis often occurs after intravenous administration.
thyroid
Hyperthyroidism can occur after stopping the drug. Except for exophthalmia signs, typical symptoms of hyperthyroidism can occur. The incidence is about 1 to 5%. It can completely disappear within weeks to months after stopping the drug. A few need to be treated with antithyroid drugs, propranolol or adrenocortical hormones;
Hypothyroidism is more common in the elderly, and typical signs of hypothyroidism may appear. It may resolve within a few months after stopping the drug, but myxedema may persist and can be treated with thyroxine.
Gastrointestinal tract, liver
Constipation, a few people have nausea and vomiting:
Hepatitis or fatty infiltration, increased transaminase, are related to the course of treatment and dose.
Eye
Those who took the medicine for more than 3 months had yellow-brown pigmentation in the cornea and below the 1/3 of the basal layer, which was related to the course of treatment and dose, and it happened less in children. This kind of calm matter can affect vision, but without permanent damage, it can gradually disappear after stopping the medicine. A small number of people may have halo, which can disappear after stopping or reducing the drug.
nervous system
Rarely, it is related to the dosage and treatment course, and tremor, ataxia, proximal muscle weakness, extrapyramidal signs may appear. Those who have taken the medicine for more than 1 year have peripheral neuropathy, which gradually subsides after reducing or stopping the medicine.
In the nervous system, the drug can cause reversible peripheral neuropathy, possibly due to intracellular phospholipid deposition. Five of the 50 patients in one group and 29 of the 54 patients in the other group had adverse neurological reactions such as tremor (the most common and early response), gait disorders, peripheral neuropathy, dizziness, and dizziness.
skin
Light sensitivity is related to the course of treatment and the dose. The slate blue-like pigmentation of the skin gradually fades after a long time (1-2 years) after stopping the drug. Other allergic rashes resolve quickly after discontinuation.
Respiratory system
Pulmonary adverse reactions mostly occurred in those who took a large amount of medication for a long time (0.8 to 1.2 g per day), and only occurred after one month of taking the medication. It mainly produces pulmonary interstitial or alveolar fibrous pneumonia. There are foamy macrophages and type 2 lung cell proliferation in the alveolar and interstitial cells, and there are fibroblasts and glial cells, a few lymphocytes and neutrophils, and small bronchial occlusion . Clinical manifestations include shortness of breath, dry cough, chest pain, etc., restrictive changes in lung function, increased erythrocyte sedimentation and increased white blood cells, which can cause death in severe cases. The drug needs to be discontinued and treated with corticosteroids.
Some have reported that this drug can cause interstitial pneumonia or alveolitis, and some have reported pulmonary insufficiency without pneumonia. And confirmed to be caused by toxic effects or allergic reactions. However, some people believe that this drug is caused by phospholipids. Clinical diagnosis of pneumonitis caused by amiodarone is difficult.
other
Occasionally hypocalcemia and elevated serum creatinine can occur. When intravenous administration is used to locally stimulate phlebitis, it should be diluted with sodium chloride injection or water for injection. Injecting a small amount of sodium chloride injection in situ after each intravenous injection can reduce the irritation.
Can cause gastrointestinal reactions: nausea, vomiting, loss of appetite, bloating, diarrhea. Visual impairment, thyroid dysfunction (hyperthyroidism), hyperpigmentation, exacerbation of ventricular tachycardia. May have pulmonary toxicity.
Adverse reactions include dry mouth, nausea, vomiting, constipation, bloating, loss of appetite, insomnia, dreaminess, dizziness, headache, blurred vision, orbital pain, paresthesia, ataxia, tremor, microkeratosis, and occasionally affects vision . A few have slate blue-like pigmentation, thyroid dysfunction, alveolitis, pulmonary fibrosis, and temporary impairment of liver and kidney function. The electrocardiogram showed prolonged QT interval, low T wave, notch, obvious U wave, sinus bradycardia, atrioventricular block, and hypotension. Individuals can cause apical torsional ventricular tachycardia and even induce ventricular fibrillation. Rarely, there is sinus rest. Intravenous boluses can cause atrioventricular block, hypotension, and even fatal cardiogenic shock.

Amiodarone Drug Interactions

Amiodarone strengthens the anticoagulant effect of dicoumarin and warfarin, prolongs prothrombin time, which occurs as early as 3 to 4 days after treatment, and as late as 3 weeks after treatment. This synergistic effect is sustainable For weeks or months, the maintenance of dicoumarin can be reduced by 1/3 to 1/2 after the start of treatment. This medicine can also affect heparin activity. It increased the concentration of digoxin in plasma. The concentration of digoxin in blood began to rise within 24 hours after amiodarone, rose linearly within 6 to 7 days, and then stabilized at a high level. Because it prolongs the QT interval, it has the effect of strengthening class 1 antiarrhythmic drugs. It is used in combination with quinidine, propylpramine, mexiletine, or propafenone O) and can cause torsional ventricular tachycardia and ventricular fibrillation. It is used in combination with a mother receptor blocker, which can cause inhibition of the sinoatrial node and hypotension.
The interference to experimental diagnosis is manifested in the following aspects.
ECG changes: For example, the interval between PR and QT is prolonged. Most patients have T wave reduction with widening and two-way, and U wave appears after taking the medicine. This is not an indication of withdrawal.
Very few AST, ALT and alkaline phosphatase increase.
Changes in thyroid function. This product inhibits the conversion of surrounding T4 to T3, leading to an increase in T4 and a slight decrease in serum T3. Thyroid function tests are usually abnormal, but there is no clinical thyroid dysfunction. Abnormal thyroid function tests can persist for weeks or months after discontinuation.
Anticoagulant
Increase the anticoagulant effect of warfarin, this effect can be from 4 to 6 days after the addition of this product, and lasts to weeks or months after stopping the drug. Anticoagulants should be reduced by 1/3 to 1/2 when combined, and prothrombin time should be closely monitored. This product is used in combination with warfarin, which can cause bleeding due to the binding effect of competing proteins. In combination with beta-blockers, it can cause significant bradycardia. Combined with verapamil, occasionally can cause cardiac arrest. Combined with quinidine, digoxin, amprolidine, propidamine, procainamide, and propafenone, the QT interval can be prolonged, and apical torsional ventricular tachycardia can be induced. Synergistic anti-arrhythmic effect with mexiletine. Combined with monoamine oxidase inhibitors, this product can reduce metabolism.
Amiodarone can strengthen the anticoagulant effect of dicoumarin and warfarin. The prothrombin time is prolonged, occurring as early as 3 to 4 days after treatment, and as late as 3 weeks after treatment. This synergistic effect can be It lasts for weeks or months, so after the start of treatment, the amount of dicoumarin maintenance can be reduced by 1/3 to 1/2.
This medicine can also affect heparin activity.
And antiarrhythmics
Enhance the effect of other antiarrhythmic drugs on the heart. This product can increase the concentration of quinidine, procainamide, flucarnet and phenytoin in plasma. Combination with Class IA drugs and mexiletine can aggravate QT interval prolongation, and very few can cause torsional ventricular tachycardia, so special care should be taken. Starting from the addition of this product, the original antiarrhythmic drug should be reduced by 30 to 50% of the dose, and the drug should be gradually discontinued. If the combination is necessary, the recommended dose is usually reduced by half.
Combined with -blockers or calcium channel blockers can worsen sinus bradycardia, sinus arrest and atrioventricular block. If this happens, the product or the first two drugs should be reduced.
Increasing the concentration of serum digoxin may also increase the concentration of other digitalis preparations to achieve toxic levels. When starting this product, digitalis should be discontinued or reduced by 50%. If combined, the serum concentration should be carefully monitored. This product can strengthen the inhibitory effect of digitalis on sinoatrial node and atrioventricular node. It increases the concentration of digoxin in plasma. The concentration of digoxin in blood begins to rise within 24 hours after amiodarone, and it rises linearly within 6 to 7 days, and then stabilizes at a high level.
Because it prolongs Q-Tc, it has the effect of strengthening class 1 antiarrhythmic drugs;
It is used in combination with quinidine, propidamine, bradycardia or heart rate and can cause torsional ventricular tachycardia and ventricular fibrillation.
Combined with beta-blockers, it can cause sinus node suppression and hypotension.
other
Combined with potassium excretion diuretics, can increase arrhythmia caused by hypokalemia.
Increase the effect of sun-sensitive drugs.
Can inhibit thyroid uptake of 123-I, 131-I and 99m-Tc.
Shared considerations
1. Prohibition of amiodarone in combination with drugs that cause apical torsional VT:
a. Antiarrhythmic drugs, such as diphenpyramine, class I antiarrhythmic drugs, and sotalol.
b. Non-arrhythmic drugs, such as vinblastine, sutopril, erythromycin intravenous dosage form, pentamidine (parenteral medication). Potential danger due to lethal tip torsional ventricular tachycardia.
2. The following drugs should not be used in combination with amiodarone:
a. Beta-blockers and calcium channel antagonists, such as verapamil, thiazezone. Due to possible disturbances of autonomy (severe bradycardia) and conduction disorders.
b. Irritating laxatives. Because it can cause hypokalemia, increasing the risk of tip-torsional ventricular tachycardia.
3 The following drugs need special attention when used in combination with amiodarone:
a. Drugs that can cause hypokalemia:
Diuretics (single or combined); corticosteroids (glucocorticoids and mineralocorticoids), tecocortin;
Amphotericin B intravenous dosage form.
Hypokalemia must be prevented, and hypokalemia should be corrected if necessary; QT intervals should be monitored. Once the apical torsional ventricular tachycardia occurs, anti-arrhythmic drugs should not be applied (a shaker and magnesium supplementation should be placed).
b. Oral anticoagulant drugs are at increased risk due to anticoagulant therapy. When combined with amiodarone or after discontinuation of amiodarone, the prothrombin levels should be closely monitored and the amount of oral anticoagulant drugs adjusted.
c. Digitalis may have autonomic disturbances (severe bradycardia) and atrioventricular conduction disorder (synergy). In addition, the blood concentration of digoxin may increase (due to the reduction of digoxin clearance). Clinically, the electrocardiogram and biochemical examination (including digoxin blood concentration), adjust the digoxin dose if necessary.
d. Phenytoin can increase the blood concentration of phenytoin and is accompanied by excessive signs (especially signs of the nervous system). Clinical monitoring should be performed. In case of excessive signs, phenytoin dose should be reduced and phenytoin blood concentration should be measured.
e. Patients under general anesthesia and general anesthesia with oxygen therapy may have serious complications, such as bradycardia, hypotension, conduction disturbance, and low cardiac output that are not responding to atropine. A few severe respiratory comorbidities (acute adult distress syndrome) are sometimes life-threatening, and most of them occur immediately after surgery, which may be related to high-oxygen interactions. Therefore, the anesthesiologist should be notified that the patient is using amiodarone before surgery.
f. Cyclosporine can increase cyclosporin blood concentration. This is related to the decline in drug clearance, so adjust the cyclosporine dose.

Amiodarone Expert Reviews

Amiodarone is used as a vasodilator for angina pectoris. In 1969, amiodarone was found to have significant antiarrhythmic effects. In cases where a variety of antiarrhythmic drugs have been ineffective for a long time, switching to amiodarone can work, which is particularly valued. A large number of basic and clinical studies have proven that amiodarone has the effects of all four types of antiarrhythmic drugs. It has a significant effect on the maintenance of sinus rhythm in patients with persistent tachycardia, atrial fibrillation and atrial flutter after reversion, without increasing mortality. However, the toxic and side effects of amiodarone are complicated, and it is necessary to pay close attention during application.

Amiodarone poisoning

Amiodarone (ethylamiodarone, clodron) has an antiarrhythmic effect, and is clinically used to treat ventricular, supraventricular tachycardia, prephase contraction, and paroxysmal atrial flutter. Pre-excitation syndrome, etc.
Orally take 0.1 0.2g, 3 4 / d each time, and then change it to 0.2g, 1-2 / d each time. Intravenous injection or intravenous drip is mainly used for immediate arrhythmia and cardioversion, 5 to 10 mg / kg, divided into 2 to 3 doses, and diluted slowly with 50% glucose solution (10 to 15 min). After diluting with 250ml glucose solution, the dripping was completed within 30min. The drug is well absorbed orally, and its blood concentration reaches its peak in 6-8 hours. It is metabolized in the liver and excreted by the liver and bile. The average half-life is 52.6 days.
Human poisoning blood drug concentration is 2.5 g / ml. Mice were injected intraperitoneally with LD500.432g / kg and intravenously with LD500.1669g / kg. This medicine mainly damages the heart, digestive system, nervous system and causes allergic reactions.
Clinical manifestation
Adverse reaction
Such as dizziness, nausea, vomiting, constipation, bradycardia, corneal lesions, and decreased vision.
2. Poisoning performance
(1) Cardiovascular system: Inhibition of sinoatrial node function or atrioventricular block and torsional ventricular tachycardia, ECG shows prolonged QT interval, low T wave, U wave, and hypotension and heart failure can be seen by intravenous injection too fast.
(2) Nervous system: tremor, ataxia, extrapyramidal symptoms, polyneuritis. (3) Digestive system: nausea, vomiting, constipation, elevated transaminase, etc.
(4) Endocrine system: hyperthyroidism or hypothyroidism, myxedema.
(5) Respiratory system: interstitial pneumonia or alveolar fibrous pneumonia, dissemination of tuberculosis, and pleural effusion. (6) Blood system: rapid erythrocyte sedimentation, increased white blood cells, and thrombocytopenia.
(7) Allergic reactions: skin photosensitivity, acute iodine allergic reaction, asthma, etc. (8) Others: manifestations of nephrotoxicity, stuttering, breast development, corneal lesions, etc.
treatment
The main points of treatment of amiodarone poisoning are:
1. Stop poisoning immediately if a poisoning reaction occurs.
2. Allergic reactions can use antihistamine drugs or prednisone, hydrocortisone, dexamethasone and so on. Corneal lesions can be spotted with 1% methylcellulose or sodium iodoparin.
3. Bradycardia, anisodamine, isoprenaline and dexamethasone can be used, and a pacemaker can be placed if necessary.
4. Glucocorticoids are available for lung lesions.
5. Induced hyperthyroidism, using hyperthyroidism drug replacement therapy, severe surgery.
6. Liver dysfunction should be treated with liver-protective drugs.
7. Other symptomatic treatments [2] .

Amiodarone injection preparation

ingredient
This product is mainly divided into [3] divided into amiodarone hydrochloride, prescription: 150mg of amiodarone hydrochloride, 60mg of benzyl alcohol, polysorbate 80,300mg, water for injection is added to 3.0ml, and nitrogen is appropriate.
specification
3ml: 0.15g
[Character]
This product is a pale yellow clear liquid.

Amiodarone Pharmacology and Toxicology

This product is a class III antiarrhythmic drug. The main electrophysiological effect is to prolong the action potential duration and effective refractory period of each cardiac muscle tissue, slow down the conduction, and help to eliminate reentry excitement. It also has mild non-competitive and adrenergic blockade and mild class I and IV antiarrhythmic drugs. Reduce the sinus node self-discipline. It has no effect on resting membrane potential and action potential height. Atrioventricular bypass inhibits forward conduction more than reverse. The effect of excessive prolongation of repolarization was not obvious in the short-term intravenous injection. Intravenous injections have mild negative muscle strength but usually do not inhibit left ventricular function. Originally angina pectoris, it has selective direct expansion of coronary arteries and surrounding blood vessels, can increase coronary blood flow, and reduce myocardial oxygen consumption. Can affect thyroid hormone metabolism. This product is characterized by a long half-life, so fewer medications, a large therapeutic index, and a broad spectrum of antiarrhythmia.

Amiodarone indications

It is suitable for ventricular tachycardia ineffective for lidocaine and ventricular rate of emergency control atrial fibrillation and atrial flutter.

Amiodarone dosage

For pharmaceutical reasons, concentrations of less than 2 ampoules in 500ml should not be used. Formulated with isotonic glucose solution only. Do not add any other preparations to the infusion. Amiodarone should be administered via the central intravenous route whenever possible. The individual differences of adacorone are large, and it is necessary to give a loading dose to suppress life-threatening arrhythmia, and at the same time to make precise dose adjustments. Usually, the initial dose is 1000 mg of clozaron within 24 hours, which can be administered according to the following table. The recommended dose of Kedalong injection is the first 24 hours.
After the first 24h, maintain an infusion rate of 0.5mg / min (720mg / 24h) and a concentration of 1-6mg / ml (concentration of Kedalong injection exceeds 2mg / ml, which needs to be administered through a central venous catheter), which needs to be continued Drip. When ventricular fibrillation or hemodynamically unstable ventricular tachycardia occurs, it is possible to add 150 mg of Ketanlong injection. A glucose solution in looml was administered. It takes 10min of peony to reduce the occurrence of hypotension. The rate of maintaining the drip can be increased to effectively suppress arrhythmia.
The first 24h dose can be administered on an individual basis for patients, however, in clinical controlled studies, the average daily dose above 2100mg is associated with an increased risk of hypotension. The initial drip rate should not exceed 30 mg / min.
Based on the clinical research experience of Kedalong injection, regardless of the patient's age, renal function, and left ventricular function, maintaining an instillation of 0.5 mg / min can be continued cautiously for 2 to 3 weeks. Patients have limited experience with clodron injection over 3 weeks.
Kedalong injection should be instilled as much as possible through a central venous catheter. Kedalong injection in 5% glucose solution, when the concentration exceeds 3mg / ml, it will increase the incidence of peripheral phlebitis. If the concentration is below 2.5mg / ml, the above-mentioned cases are rare. Therefore, if intravenous drip is needed for more than 1 hour, the concentration of Ketanlong injection should not exceed 2mg / ml. Unless a central venous catheter is used.
In the application of PVC materials or equipment, the amiodarone solution can release diethyl phthalate (DEHP) into the solution. In order to reduce the patient's exposure to DEHP, it is recommended to use PVC or glassware that is reluctant to use DEHP. Dilute clodron's infusion solution.
Cardiopulmonary resuscitation of ventricular fibrillation-associated cardiac arrest with ineffective external defibrillation.
According to the administration route of amiodarone and considering the application status of this indication, if it can be obtained immediately, the use of a central venous catheter is recommended; otherwise, the largest peripheral vein is used and the peripheral vein route is used at a high flow rate. The initial intravenous dose was 300 mg (or 5 mg / kg), diluted in 20 ml of a 5% glucose solution and injected quickly. If ventricular fibrillation persists, an additional 150 mg (or 2.5 mg / kg) of the intravenous route should be considered. No other medicines may be added to the syringe.

Amiodarone adverse reactions

1. Cardiovascular system: Compared with other antiarrhythmic drugs, it has fewer adverse cardiovascular effects. mainly include:
(1) Atropine cannot counteract this response due to sinus bradycardia, transient sinus arrest, or sinoatrial block.
(2) Atrioventricular block.
(3) Occasionally prolonged QT interval with torsional ventricular tachycardia.
(4) Arrhythmogenic effects, especially prone to occur when long-term high doses are accompanied by hypokalemia.
(5) Hypotension occurs during intravenous injection. When torsional ventricular tachycardia develops into ventricular fibrillation, it can be converted by direct current. Due to the long half-life of this product, adverse reactions to treatment need to last 5 to 10 days.
2. thyroid
(1) Hyperthyroidism can occur after discontinuation of the drug, in addition to exophthalmia signs, typical signs of hyperthyroidism, new arrhythmia can occur, T3 and T4 are increased, and TSH is decreased. The incidence is about 2%. It can completely disappear within weeks to months after stopping the drug. A few patients need to be treated with antithyroid drugs, propranolol or adrenal corticosteroids.
(2) Hypothyroidism, with an incidence of 1% to 4%. It is more common in the elderly. Typical signs of hypothyroidism may appear, TSH decreases, and it may resolve within a few months after stopping the drug, but myxedema may be left untreated and necessary Can be treated with thyroxine.
3 Gastrointestinal tract: constipation, a few people have nausea, vomiting, decreased appetite, and the load is obvious.
4 Nervous system: Rarely, it is related to dosage and course of treatment. It may appear tremor, ataxia, weakness of proximal muscles, extrapyramidal signs.
5. Skin: Light sensitivity is related to the course of treatment and dosage. The slate blue-like pigmentation of the skin gradually fades after a long time (1 to 2 years) after drug withdrawal. Other allergic rashes resolve quickly after discontinuation.
6. Liver: Hepatitis or fatty infiltration, increased aminotransferase, and related to the course of treatment and dose.
7. Lungs: Adverse reactions in the lungs occur mostly in those who take large amounts of drugs for a long time (0.8 to 1.2 g per day). It mainly produces allergic pneumonia and causes fibrotic alveolitis. The lesions showed alveolar and interstitial foam-like macrophages and type 2 lung cell hyperplasia, fibrosis, and small bronchial lumen occlusion. Clinical manifestations include chest tightness, shortness of breath, dry cough, and chest pain, which can cause death. Laboratory tests can show restricted pulmonary ventilation dysfunction, increased erythrocyte sedimentation, and increased white blood cells. Patients with the above symptoms in the lungs discontinued and were treated with corticosteroids.
8. Others: occasionally hypocalcemia and elevated serum creatinine may occur. When intravenous administration is used to locally stimulate phlebitis, it should be diluted with sodium chloride injection or water for injection, or centrally administered.

Amiodarone Taboo

1. Severe sinus node dysfunction is disabled.
2. or degree atrioventricular block, double beam branch block (unless a pacemaker) is disabled.
3 Bradycardia caused by syncope are disabled.
4 Diffuse pulmonary interstitial fibrosis is disabled for various reasons.
5. Those who are allergic to this product are prohibited.

Amiodarone precautions

1. Cross-allergic reactions: Those who are allergic to iodine may be allergic to this product.
2. The following situations should be used with caution:
(1) Sinus bradycardia.
(2) QT interval prolongation syndrome.
(3) Hypotension.
(4) Liver insufficiency.
(5) Pulmonary insufficiency.
(6) Severe congestive heart failure.
3 Interference to diagnosis:
(1) ECG changes: For example, the PR and QT intervals are prolonged. After treatment, patients may have a decrease in T waves with a widening and two-way u waves. This is not an indication of discontinuation.
(2) Rarely, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase are increased.
(3) Changes in thyroid function. This product inhibits the conversion of surrounding T4 to T3, leading to an increase in T4 and rT3 and a slight decrease in serum T3. The thyroid function tests are usually abnormal, but there is no clinical thyroid dysfunction. Abnormal thyroid function tests can persist for weeks or months after discontinuation.
4 Blood pressure and electrocardiogram should be monitored during medication; follow-up examination should be paid attention: liver function, thyroid function (including T3, T4 and thyroid stimulating hormone, once every 3 to 6 months), lung function and chest X-rays (every 6-12) 1 time a month) and for eye examination.
5. This product has a long half-life, so you should pay attention to the interaction when switching to other antiarrhythmic drugs after discontinuation.
[Medication for pregnant and lactating women]
Pregnancy: Animal studies have not provided evidence that this product has teratogenic effects and can be expected to have no teratogenic effects on humans. In fact, to date, drugs that have teratogenic effects on humans have been shown to have teratogenic effects in two rigorous animal studies.
Given the effects of amiodarone on the fetal thyroid, its use is prohibited during pregnancy unless its benefits outweigh its disadvantages.
Breastfeeding: Amiodarone and its metabolites, as well as iodine, are more concentrated in breast milk than in blood. Because of the risk of hypothyroidism in newborns, this product is contraindicated to thousands of nursing mothers.
[Child medication]
The safety and effectiveness of amiodarone hydrochloride in pediatric patients has not been established and therefore is not recommended for children. Amiodarone for injection contains benzyl alcohol, and neonates (papillary infants born less than one month old) have reported wheezing and lethality after intravenous administration. Symptoms include respiratory asthma, hypotension, arrhythmia, and cardiovascular failure.

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