Dive Health & Safety
Taking medicine before a dive: antihistamines, decongestants and painkillers
Diving on most medicines is something to discuss with your doctor first, says Divers Alert Network. Antihistamines can make you drowsy and slow your thinking; decongestants can cause a racing heart; painkillers can mask the early pain of decompression illness. Many diving doctors advise waiting until an illness is over rather than diving while you need the medicine.
By 71 Guardians · Published 19 Oct 2026
Should I dive while taking medicine?
DAN says it's a matter for you and your doctor. Many diving-medicine doctors suggest waiting until the illness is over instead. Starting a medicine at least a day or two before diving helps you see how you react — but reactions underwater can't be predicted.
Which medicines cause problems?
- Antihistamines: drowsiness, dry mouth and blurred vision; they can impair a diver's ability to think clearly and react.
- Decongestants: nervousness, dizziness and a rapid or pounding heartbeat — divers with diabetes, asthma or heart disease may need to avoid them.
- Painkillers and anti-inflammatories: can mask mild pain from decompression illness and delay treatment.
- Seasickness medicines: guidelines say to consult a doctor first because of drowsiness.
Frequently asked questions
Can I take ibuprofen after diving?
Be aware it can mask mild decompression-illness pain. If you have unusual pain after diving, get advice rather than just a painkiller.
Is it OK to dive with a cold on decongestants?
See our article Can you scuba dive with a cold? — decongestants can wear off at depth.
Questions before you dive with us?
Message our team on WhatsApp — we're divers in Hurghada and happy to help.
Chat with us on WhatsAppSources
- Over-the-Counter Medications — Divers Alert Network (DAN)