Can I take antihistamines with alcohol?

Why this happens

Both alcohol and antihistamines act as 'depressants' on the central nervous system. This means they both slow down brain activity. When taken together, they have an 'additive effect', meaning they reinforce each other's side effects, making the sedation much more powerful than if you took either one alone.

What you should do

It is best to avoid or strictly limit alcohol when taking any antihistamine. Do not drive, operate machinery, or perform tasks that require you to be alert if you have consumed alcohol while taking this medication. If you are taking an older, sedating antihistamine (often found in night-time cold and flu remedies), you should avoid alcohol entirely.

Important precautions

Central Nervous System Depression

Combining alcohol with antihistamines (especially older types like chlorphenamine or promethazine) significantly increases drowsiness, impairs coordination, and can dangerously slow your breathing. Do not drive or operate machinery if using both.

More about Alcohol

More about Antihistamines

Glaucoma and Urinary Retention

Sedating antihistamines can worsen narrow-angle glaucoma and cause severe difficulty passing urine, particularly in men with an enlarged prostate.

Food and drink warnings

Fruit Juices (Grapefruit, Orange, Apple)

Do not drink grapefruit, orange, or apple juice while taking fexofenadine. These juices can significantly reduce the amount of medicine your body absorbs, making the treatment less effective. It is best to take fexofenadine with water.

More about Fexofenadine (Allegra)

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.