Terfenadine
Terfenadine was a second-generation antihistamine used to treat symptoms of allergic conditions such as hay fever, seasonal allergies, and chronic allergic skin reactions. It worked by blocking histamine H1 receptors, reducing symptoms like sneezing, itching, and runny nose. The medication was withdrawn from markets in many countries in the late 1990s due to risk of serious cardiac arrhythmias.
Terfenadine was an antihistamine used for allergies that was withdrawn from most markets due to cardiac safety concerns.
Key facts at a glance
- ATC
- R06AX12
- RxNorm
- 42330
- Generic
- Terfenadine
- Class
- atc-r06
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Terfenadine was primarily used to treat seasonal allergic rhinitis (hay fever), perennial allergic rhinitis, and chronic idiopathic urticaria (hives). It provided relief from sneezing, nasal itching, runny nose, watery eyes, and itchy skin associated with allergic reactions.
As a selective H1-receptor antagonist, terfenadine worked by competitively blocking histamine at H1 receptor sites in blood vessels, smooth muscle, and sensory nerves. This prevented histamine from binding and triggering allergic symptoms. Unlike first-generation antihistamines, it did not significantly cross the blood-brain barrier, resulting in less drowsiness.
Terfenadine was withdrawn from the U.S. market and many other countries in 1997-1998 due to risk of serious cardiac arrhythmias (torsades de pointes), particularly when taken in overdose or combined with drugs that inhibit its metabolism (such as ketoconazole, erythromycin, or grapefruit juice). It has been replaced by fexofenadine, its active metabolite, which provides the same therapeutic benefits without the cardiac risks.
Official drug label
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This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 20, 2026. · Read our editorial policy