What Is Pheniramine Maleate?

Chlorpheniramine maleate preparations include tablets and injections, also known as chlorpheniramine, an antihistamine. It is mainly used for rhinitis, skin and mucous membrane allergies, and relief of cold symptoms such as tearing, sneezing and runny nose.

Chlorpheniramine maleate

Chlorpheniramine maleate preparations are tablets, injections, also known as

1. For allergic rhinitis.

2. Hives.

3. Various allergic skin diseases.

[Molecular formula and molecular weight] C16H19ClN2.C4H4O4, 390.87

This product is N, N-dimethyl-- (4-chlorophenyl) -2-pyridinepropylamine maleate. Calculated as dry product, including

C16H19ClN2.C4H4O4 shall not be less than 98.5%.

[Content determination] Take about 0.15g of this product, accurately weigh, add

This product is white crystalline powder; odorless and bitter.

This product is soluble in water, ethanol or chloroform, slightly soluble in ether.

Melting point The melting point of this product (Appendix VI C) is 131 to 135 ° C.

The absorption coefficient is taken from this product and accurately weighed. Add hydrochloric acid solution (dilute hydrochloric acid 1ml and water to 100ml) to dissolve and determine

Diluted to make a solution containing about 20g per 1ml, according to spectrophotometry (Appendix IV A), at a wavelength of 264nm

The absorbance was measured at the place, and the absorption coefficient (E1% 1cm) was 212 to 222.

Method Name: Chlorpheniramine Maleate-Determination of Chlorpheniramine Maleate-Non-aqueous Titration

Scope of application: This method uses the titration method to determine the content of chlorpheniramine maleate in chlorpheniramine maleate.

This method is applicable to chlorpheniramine maleate API.

Principle of the method:

In addition to blocking the histamine H1 receptor on allergic target cells, this product has an anti-allergic effect by antagonizing the H1 receptor, and also has an anti-M choline receptor effect. Later, symptoms such as dry mouth, constipation, thickened sputum, and dry nasal mucosa may appear. In addition, the drug also has a certain inhibitory effect on the center, so the drowsiness adverse reaction after taking the drug can occur.

Chlorpheniramine maleate in vivo processes

It is absorbed quickly and completely after oral and injection, with a protein binding rate of 72%. The oral onset time is 15 to 60 minutes, the blood concentration reaches a peak in 3 to 6 hours, and the intramuscular injection onset time is 5 to 10 minutes. The half-life is 12 to 15 hours, which can be maintained in the body for 3 to 6 hours. Most of the drug is metabolized by the liver in the body, and most of it is excreted by the kidneys after 24 hours. It can also be excreted through stool and sweat. Breastfeeding women can also excrete part of their milk.

Clinical effects of chlorpheniramine maleate

1. Rhinitis: effective for perennial allergic rhinitis, seasonal allergic rhinitis, vasomotor rhinitis; can also be used for nasal mucosal congestion and sinusitis caused by respiratory infections.

2. Skin and mucous membrane allergies: mainly used for allergic diseases of the skin and mucous membranes, such as angioedema, hay fever, allergic conjunctivitis, etc., and can alleviate skin itching and edema caused by insect biting dermatitis and contact dermatitis .

3. Childhood diseases: In addition to being effective for children's upper respiratory tract infections, it can also be used for gastrointestinal allergic diseases.

4. Drug reaction: used to prevent drug rash and other symptoms caused by blood transfusion, infusion reaction and drug reaction.

5. Combined medication: used in combination with compound aspirin or other antipyretic and analgesics to treat colds, relieve tears, sneeze, runny and other cold symptoms.

6. Others: Liu Guangxu used chlorpheniramine to treat urinary frequency, enuresis, and fecal incontinence caused by psychotropic drugs. In addition, Tang Baiying and Lu Dazhen reported that the drug combination and conventional treatment methods can achieve good results in chronic hepatitis.

Precautions for chlorpheniramine maleate

1. Cross-allergy: People who are allergic to other antihistamines or the following drugs may also be allergic to this drug. Such as ephedrine, epinephrine, isoproterenol, metaisoproterenol (hydroxyasthma), norepinephrine and other sympathomimetic drugs. People who are allergic to iodine may also be allergic to this product.

2. A small amount of chlorpheniramine can be excreted from breast milk. The anti-M-choline receptor effect of this product can inhibit lactation. It should not be taken casually by lactating women. This product is not suitable for newborns and premature infants. In addition, pregnant women can affect the fetus via cord blood, so women should not take it during pregnancy.

3. Elderly people are more sensitive to the commonly used dose and should pay attention to reduction.

4. The following conditions should be used with caution: bladder neck obstruction, pyloric duodenal obstruction, pylori stricture caused by peptic ulcer, cardiovascular disease, glaucoma (or those with glaucoma tendency), hypertension, hypertension crisis, thyroid When the symptoms of hyperfunction and prostatic hypertrophy are obvious.

5. This medicine should not be combined with meperidine, atropine and other drugs, nor should it be mixed with aminophylline for injection.

6. Drivers, aerial operators, machinery operators and athletes before the competition should not take this medicine.

7. People with poor liver function should not use this medicine for a long time.

8. If you take too much of this product or have serious adverse reactions, please consult a doctor immediately. Rescue of poisoned patients should not be detoxified with histamine injection.

Contraindications

1. Newborns and preterm infants, patients with epilepsy, and those receiving monoamine oxidase inhibitor therapy are contraindicated.

2. Those who are allergic to this product and accessories are prohibited.

Precautions

1. Be used with caution in infants and young children, pregnant women, closed-angle glaucoma, bladder neck or pyloric duodenal obstruction or peptic ulcer caused by peptic ulcer, cardiovascular disease patients and liver dysfunction.

2. The elderly should reduce the amount.

3. Use with caution in pregnant and lactating women.

medicine interactions

1. Combined with central nervous system inhibitors, it can strengthen the central inhibitory effect of this product.

2. It can enhance the efficacy of amantadine, haloperidol, anticholinergics, tricyclic antidepressants, phenothiazines and sympathomimetics.

3. Combined with quinidine, it can enhance the anticholinergic effect of this product.

4. This product can increase the absorption and efficacy of chloroquine, thereby improving the cure rate of parasitic diseases.

5. This product can inhibit liver microsomal enzymes that metabolize phenytoin. When combined, it can cause phenytoin accumulation and poisoning. Care should be taken to monitor the concentration of phenytoin.

6. This product should not be used in combination with pethidine and atropine, and it should not be mixed with aminophylline for injection.

7. This product has antagonism with propranolol.

[Dosing instructions] May be taken with food, water or milk to reduce gastric irritation.

[Usage and dosage]

1. Oral, 4-8mg once a day, 3 times a day.

2. Intramuscular injection, 5-20mg at a time.

[Preparation and specifications]

1. Chlorpheniramine maleate 4mg.

2. Chlorpheniramine maleate injection 1ml: 10mg; 2ml: 20mg.

Adverse reactions of chlorpheniramine maleate

1. Digestive system: Adverse reactions such as loss of appetite, nausea, epigastric discomfort or stomach pain may occur after taking the medicine.

2. Urinary system: symptoms such as dysuria and dysuria may occur when overdose.

3. Psychiatric symptoms: Mainly manifested as irritability. In the case of overdose, first central inhibition and later central excitement may occur, which may even cause convulsions and convulsions. Children are prone to anxiety, difficulty falling asleep, and nervousness.

4. Some people may also experience chest tightness, dry mouth and nose mucosa, sticky sputum, sore throat, fatigue, weakness, palpitations or skin ecchymosis and bleeding tendency after taking medicine.

[Drug overdose and treatment] When this product is poisoned, it shows: dilated pupils, flushing, hallucinations, excitement, ataxia, convulsions, and finally coma, heart and respiratory failure and death.

Symptomatic treatment and supportive therapy should be taken during rescue. When convulsions occur, thiopental sodium may be administered as appropriate to control. Do not use histamine as an antidote.