Frequently asked questions about using Chlorpheniramine

Posted by Pharmacist Hoang Nguyen Kim Thoa - Faculty of Pharmacy - Vinmec Times City International General Hospital

The most common side effect of using chlorpheniramine is drowsiness (incidence >10%), you may experience mild to moderate drowsiness when taking the drug. On the market, chlorpheniramine is available as an oral tablet, oral syrup or in combination in preparations for the treatment of cold and flu symptoms.

Chlorpheniramine is a 1st generation antihistamine, used in the treatment of allergic symptoms such as hives, urticaria, allergic rhinitis or used to relieve symptoms of the common cold. The drug works through competition for the site of action with histamine, a chemical mediator that causes allergic reactions.
On the market , chlorpheniramine is available in the form of tablets , oral syrup or in combination in preparations for the treatment of colds and flu symptoms .
Do not take chlorpheniramine if you are hypersensitive to any of its ingredients, have angle-closure glaucoma, symptomatic prostatic hypertrophy, pyloric obstruction, obstructive peptic ulcer or bladder neck obstruction. Talk to your doctor if you have respiratory problems such as emphysema, chronic obstructive pulmonary disease, or uncontrolled asthma. Chlorpheniramine should be used with caution in children < 2 years of age, especially in neonates. Only use on these subjects when prescribed and closely monitored by a doctor.

The most common side effect of using chlorpheniramine is drowsiness (incidence >10%), you may experience mild to moderate drowsiness when taking the drug. Do not operate machinery while taking this medicine. In addition, the drug can cause digestive disorders, dizziness, nausea, fatigue, increased appetite, dry mouth, urinary retention, visual disturbances (double vision).
Not all patients experience side effects from medications. If you experience any discomfort or abnormality after taking the medicine, you should talk to your doctor or pharmacist for advice.

Chlorpheniramine may interact with medications you are taking. Interactions can increase the risk of side effects from medications, including serious side effects. You should talk to your doctor and pharmacist before using chlorpheniramine if you are taking sedatives, antipsychotics, anxiolytics, anticonvulsants, opioid pain relievers and all medications you are taking, especially if the effects are not known.

The usual dose of chlorpheniramine should not exceed 24 mg/day in adults and children >12 years of age; not more than 12mg/day in children 6-12 years old; no more than 6mg/day in children 2-6 years old. The dose is usually divided 3-4 times a day, not more than 4 times in 24 hours. Children under 6 years of age should not self-medicate without a doctor's prescription. Household spoons should not be used to measure medicine in syrup form for children due to the increased risk of overdose.

The use of multiple flu preparations should be avoided due to the risk of drug duplication and possible overdose.
Overdose symptoms may include: Drowsiness (severe), confusion, weakness, blurred vision, dilated pupils, dry mouth, fever, tremors, hallucinations, convulsions... You need nearest medical facility, bring used medicine if there is a symptom of drug overdose for timely treatment

Talk to your doctor and pharmacist about any chronic medical conditions, pregnancy, lactation and medications you are taking before taking the medicine
Avoid alcohol while taking the medicine Do not exceed the prescribed dose prescription or recommended dose in the instruction sheet Tell your doctor if you experience any discomfort or abnormality after using the drug Vinmec International General Hospital with its medical facilities and equipment With modern medical facilities and a team of experts and doctors with many years of experience in medical examination and treatment, patients can rest assured that they will be examined and treated at the Hospital.
To register for examination and treatment at Vinmec International General Hospital, you can contact Vinmec Health System nationwide, or register online HERE.

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