What Is the Connection between Penicillin and Amoxicillin Allergies?

Penicillins are a class of antibiotics, including natural penicillins, enzyme-resistant penicillins, and broad-spectrum penicillins. Penicillin antibiotics include natural penicillins, such as penicillin G; enzyme-resistant penicillins, such as benzyl penicillin; and broad-spectrum penicillins, such as ampicillin, ampicillin, amoxicillin (amoxicillin), etc. ^[1] . Because of its -lactam ring in its structure, it is also called -lactam antibiotics. The role of penicillins is to interfere with the synthesis of bacterial cell walls, while mammalian cells do not have cell walls. Therefore, penicillins have low toxicity to the human body. Penicillins that have reached an effective bactericidal concentration have little effect on human cells.

Drug Name: Penicillins
Whether prescription drugs: prescription

Dosage form: Injection, tablet
Athletes use with caution: Use with caution
Whether to include health insurance: Incorporate

Penicillin I. Classification

oral acid-resistant penicillin: commonly used drugs are penicillin V.

Enzyme-resistant penicillin: commonly used drugs are methicillin, oxacillin, clozacillin, and dicloxacillin.

broad-spectrum penicillins: commonly used drugs are ampicillin and amoxicillin.

Anti-Pseudomonas aeruginosa penicillins: commonly used drugs are carbenicillin and piperacillin.

Anti-gram-negative bacilli penicillins: commonly used drugs are mecillin and temocillin. It is characterized by being more resistant to enzymes and effective on certain negative bacilli (such as large intestine, Klebsiella and Salmonella), but ineffective against Pseudomonas aeruginosa.

Natural penicillins: such as penicillin G, commonly used drugs include penicillin G potassium, penicillin G sodium, and long-acting cilin.

Penicillin II. Characteristics

Penicillin antibacterial drugs can kill bacteria by interfering with the cell wall synthesis of bacteria.

Penicillin drugs have a strong effect on bacteria that are synthesizing a large number of cell walls during reproduction, and

The bacteria that form the cell wall and are in the stationary phase are weak, so they belong to the breeding period fungicide.

Natural penicillin is not resistant to acid and penicillinase and has a narrow antibacterial spectrum.

Penicillin V is an acid-resistant oral penicillin.

Penicillin-resistant penicillin such as methicillin and oxacillin, it is golden yellow to produce penicillinase.

Staphylococcus has a better effect.

B-lactamase inhibitor (clavulanic acid, sulbactam, tazobactam) and penicillin

Prescriptions, which protect the structure of enzyme-resistant antibacterial drugs from destruction, play an important role in the clinic. ^[2]

Penicillins III. In vivo processes

The gastrointestinal tract absorbs well, and food residues will affect its absorption. Therefore, the drug should be taken on an empty stomach one hour before a meal. The blood concentration reaches a peak in about 1 to 1.5 hours, and the effective concentration can be maintained for 2 to 3 hours. Among the drugs, oxacillin was the worst, followed by clozacillin, and diclocillin was the best. Plasma protein binding rates were high (more than 95%). It is mainly excreted from the urine as a prototype and is slower than penicillin. ^[3]

Penicillin IV. Dosage and Formulation

1. Penicillin usage and dosage are as follows:

Intramuscular injection: every 500,000 U is dissolved in 1 ml of water for injection. If it exceeds 500,000 U, 2 ml of water for injection is required. Sodium chloride injection is not used as a solvent. Adults: 800,000 to 2 million U / day, divided into 3 to 4 Intravenous infusion: 2 million to 20 million U / day for adults, divided into 2-4; Children divided into 2-4 times according to 50,000 u to 200,000 u / (kg · d) Light, moderate Renal dysfunction does not decrease; infusion rate cannot exceed 500,000 U / min.

Penicillin preparation specifications are as follows:

Powder injection for injection (sodium penicillin): 0.12g (200,000 U); 0.24g (4 million U) for injection (penicillin potassium): 0.1259 (200,000 U);

0.6259 (1 million U)

2. The dosage of amoxicillin is as follows:

Oral: 0.5g / time for adults, once every 6 to 8h, not more than 4g / d intramuscularly or intravenously: 0.5-1g / time for adults, once every 6-8h; after each hemodialysis Give 1g.

Amoxicillin formulation specifications are as follows: tablets: 0.125g; capsules: 0.125g; dry suspension: 0.125g; bottled: 1.25g. Granules: 0.125g; powder injection for injection: 0.5g. ^[4]

Penicillins 5. Clinically significant drug interactions

Clinical significance

(1) Combined with probenecid, aspirin, indomethacin, butasone and sulfa drugs, can reduce penicillin

The renal tubules secrete and prolong their plasma half-life.

(2) Combined with warfarin, it can enhance the anticoagulant effect of the latter.

2. Clinically significant drug interactions

(1) Combined with probenecid, aspirin, indomethacin, butasone and sulfa drugs, can reduce penicillin

The renal tubules secrete and prolong their plasma half-life.

(2) Combined with warfarin, it can enhance the anticoagulant effect of the latter.

Penicillin class 6. Typical adverse reactions and contraindications

(1) Adverse reactions

Penicillins can have severe allergic reactions, such as anaphylactic shock (type I allergy) and blood

Clear disease type response (type III allergy).

Other allergic reactions include hemolytic anemia (type II allergy), decreased white blood cell count, drug rash, urticaria

Measles, contact dermatitis, asthma attacks, etc.

A large amount of penicillin sodium can cause hypernatremia.

When a large amount of penicillin potassium salt is used, hyperkalemia or potassium poisoning can occur.

Long-term and high-dose medications can cause dysbiosis and a double infection caused by Candida or drug-resistant bacteria. ^[2]

Patients with positive penicillin skin test are prohibited.

Penicillin VII, medication monitoring

1. Ask about allergies before taking medication

(1) Penicillins can cause severe allergic reactions.

(2) Intradermal injection of a penicillin solution with a concentration of 250-500U / ml is used for injection of 0.05 o.1 "for skin

Sensitive test.

(3) Regardless of the route of administration, skin must be skinned before applying penicillin and penicillin compound preparations.

Skin sensitivity test.

(4) Once anaphylactic shock occurs, it must be rescued locally, and the patient is injected subcutaneously with epinephrine.

Oxygen, anti-shock treatment with vasoactive drugs, glucocorticoids, etc. ^[2]

2. Choose the right solvent and drip rate

(1) The solvent should be 0.9% sodium chloride injection (pH 5.0 7.5)

(2) The volume of a single dose is 50 200ml, it should not exceed 200ml.

(3) It should be prepared fresh.

(4) The intravenous drip time should not exceed 1h.

(5) Penicillin potassium salt cannot be injected intravenously or intravenously.

3 Monitoring special reactions to penicillins

(1) Systemic application of large doses of penicillin can cause increased tendon reflexes, muscle spasms, convulsions, coma, etc.

Central nervous system response (penicillin encephalopathy).

(2) Penicillin cannot be used for intrathecal injection.

(3) Large amounts of penicillin potassium and sodium salts can cause electrolyte disturbances.

(4) When penicillin is used to treat syphilis, leptospirosis, etc., symptoms can be caused by pathogen death

Aggravated, known as the Jihai reaction (Hirschmann reaction). ^[2]

Penicillins 8. Pay attention to the use of penicillins

(1) Although penicillin drugs are less toxic, a few people are allergic to this class of drugs, such as rash, drug fever, asthma, angioedema, and even anaphylactic shock. The latter is the most dangerous, and it is often injected or skin Occurred during the test, about 50% occurred in a few seconds to 5 minutes, and the rest occurred in about 20 minutes, you should pay great attention. Those who use it after the first injection or 3 days after discontinuation should perform a skin allergy test. If the skin test is negative (can be used), but those who have chest tightness, asthma, itchy skin and other abnormal symptoms, should not be injected. After penicillin injection, it should be observed for 20 minutes. Once anaphylactic shock occurs, rescue with adrenaline, hydrocortisone, etc. immediately.

(2) The use of penicillin is getting larger and larger, and there is a tendency to use large doses (more than 10 million units) or super large doses. The use of large doses of penicillin can interfere with the coagulation mechanism and cause bleeding. Occasionally, a large amount of penicillin enters the central nervous system and causes poisoning. It can cause convulsions, radiculitis, incontinence, and even paralysis. Therefore do not increase the dose at will.

(3) Penicillin drugs should not be stored after dissolution, and should be "ready-to-use". Because the longer the penicillin solution is left to stand, the more it decomposes, and the allergens are also increasing, which may lead to a decrease in drug efficacy and the occurrence of allergic reactions.

(4) Try to avoid using penicillin topically and avoid penicillin injection when you are overly hungry. Therefore, it is easy to cause allergic reactions. ^[5]