Written & medically reviewed by Dr. Sanjay Anbu, MBBS· Last reviewed
Pheniramine (Avil) is an older, sedating antihistamine used for allergies, itching and allergic reactions. It works quickly but commonly causes drowsiness.
Typical dose — general reference only, NOT a prescription
Measure
Range
Category
Over-the-counter (OTC)
Adult dose
22.5–45 mg (e.g. Avil 25 mg) 2–3 times daily; injection used for severe allergy under care
Child (paediatric) dose
Small weight/age-based dose — doctor advice (causes drowsiness)
What it is used for
Allergic reactions, hives and itching
Runny nose and sneezing
Allergic reaction support (injection, under medical care)
Common brand names
India: Avil, Anvil
Worldwide: (pheniramine; older antihistamine class similar to Piriton)
Common side effects
Drowsiness (common)
Dry mouth
Blurred vision or constipation
Before taking it — precautions
Do not drive or operate machinery if drowsy
Avoid alcohol
Caution in the elderly, glaucoma and prostate problems
When to see a doctor urgently
Severe allergic reaction (seek emergency care for breathing difficulty/swelling)
Marked drowsiness or confusion
Doses are a general reference, not a prescription. Doses shown are typical adult/paediatric references and vary with age, weight, kidney/liver function and the exact product. Paediatric doses are usually weight-based and must be set by a doctor. MedDroid cannot prescribe — always confirm pheniramine and your dose with a doctor or pharmacist and the leaflet inside the pack.
Frequently asked questions
Why does Avil make me sleepy?
It is an older antihistamine that crosses into the brain more than newer ones, which is why drowsiness is common. Non-drowsy options like cetirizine exist.
Is Avil used for serious allergic reactions?
The injection is sometimes given as part of treating allergic reactions under medical care, but a severe reaction (anaphylaxis) is an emergency needing adrenaline.
Reviewed by Dr. Sanjay Anbu, MBBS. MedDroid is an AI medical assistant and can make mistakes. It provides general health information, not a diagnosis or medical advice — always consult a qualified clinician. In an emergency, contact your local emergency number immediately.