Adhista

Indications

Chlorpheniramine Maleate is an antihistamine used to relieve allergy symptoms such as sneezing, runny or itchy nose and watery eyes (hay fever and allergic rhinitis), itchy skin rashes and hives, insect bites, and itching from chickenpox. It is also found in many cough and cold remedies. The injection is used in hospital as an extra treatment for severe allergic reactions.

How It Works

It blocks histamine, a chemical the body releases during an allergic reaction. This reduces itching, sneezing, swelling and a runny nose. It also enters the brain, which is why it often causes drowsiness.

Dosage and Administration

Adults and children over 12 years: 4 mg every 4 to 6 hours when needed; no more than 24 mg in 24 hours. Children 6 to 12 years: 2 mg every 4 to 6 hours; no more than 12 mg in 24 hours. Children under 6 years: only as prescribed. Older people may need a lower dose. Injections are given by a doctor or nurse. Check combination cold products so that you do not take it twice.

Interactions

Alcohol, sleeping tablets, sedatives, opioid painkillers, anxiety medicines and other antihistamines increase drowsiness. Do not take it within 14 days of an MAO inhibitor antidepressant. Medicines with anticholinergic effects (such as Amitriptyline and some bladder or Parkinson's medicines) can increase dry mouth, constipation and difficulty passing urine. It may raise the level of Phenytoin.

Contraindications

• Allergy to Chlorpheniramine or other similar antihistamines.
• Use of an MAO inhibitor in the last 14 days.
• Newborn and premature babies.

Side Effects

Common: drowsiness, dry mouth, dizziness, blurred vision, headache, poor concentration and constipation. Children may become excited or restless instead of sleepy. Older people may become confused.

Stop taking it and get urgent medical help if you have:

• Swelling of the face or throat, difficulty breathing or a severe rash.
• A fast or irregular heartbeat.
• Fits, hallucinations or severe confusion.
• Being unable to pass urine.
• Severe eye pain with blurred vision.

Pregnancy and Lactation

Use in pregnancy only if a doctor or pharmacist advises it, especially in the last weeks, as it can affect the newborn. It passes into breast milk, may make the baby sleepy or irritable and may reduce milk supply, so avoid regular use while breastfeeding; ask about a non-drowsy option.

Precautions and Warnings

It can make you drowsy, so do not drive or operate machinery if affected, and avoid alcohol. Use with care in older people (risk of confusion and falls), and in people with glaucoma, an enlarged prostate or difficulty passing urine, epilepsy, asthma, heart disease, high blood pressure, an overactive thyroid, or liver disease.

Overdose

Too much can cause severe drowsiness, or in children excitement, hallucinations and fits. Other signs are a fast heartbeat, dilated pupils, flushing, fever and difficulty passing urine. This is an emergency; seek medical help at once.

Therapeutic Class

Sedating antihistamine (first-generation H1 antihistamine).

Storage

Store below 30°C in a dry place, away from light and out of the reach of children.