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Prescription drugs

Anticoagulants (Blood thinning drugs)

These are used for a variety of conditions including:

  • After a cardiac stent or heart valve replacement
  • Following a stroke or mini-stroke
  • Atrial Fibrillation or Flutter (irregular heart rhythm)
  • Deep Vein Thrombosis (DVT) or Pulmonary Embolus (PE))
  • Anti-coagulants are not all the same and each group of drugs is slightly different in the way they work. Some are considered safe to dive with but others are not.

Anti-coagulants can put you at greater risk of serious consequences should you suffer barotrauma (pressure injury) or Decompression Illness (DCI). This is because during such an injury, the amount of bleeding is increased and more damage could occur to the tissues.

Also, your overall level of fitness must be taken into account if you have any of the conditions above.

If you want to go diving on these medications you need to discuss your medical condition and the medication with a doctor specialising in diving medicine. Please arrange a telephone consultation with one of our diving doctors. (Here)

Anti-malarial tablets

We usually suggest divers take Malarone. You will have to check that this works in the area you are planning to travel to.

We also recommend starting Malarone 1 week (rather than 2 days) before your trip to ensure you do not suffer any side effects from the medication. Doxycycline would be an alternative providing it gives you adequate protection in the area you are travelling to but you must be careful to avoid sun exposure.

Larium is the anti-malarial to avoid whilst diving.

You cannot get these drugs over the counter, so see your GP or go to a travel clinic to ensure you are fully vaccinated, up to date with your immunisations and that the medication will cover you in your area of travel. We also advise buying your medications from a known reliable source such as a UK based pharmacy since the medications will be of a known, quality and standard.

Over the counter drugs

There are many medications that have now been approved to be issued direct to the public by the chemist.  Each of these drugs may or may not be advisable to take when you dive.

If you have symptoms after diving about which you are unsure – contact DDRC Healthcare urgently on 01752 209999.

If you have a new or different medical problem then you should consult your GP and establish an underlying diagnosis before diving. If it is a self-limiting illness, such as a cold/flu, you should return to diving when you feel well again and not before due to risk of barotrauma.

If you have a new medical problem that you are unsure if you are safe to dive with then please arrange a telephone consultation with one of our diving doctors. (Here)

Some medications are worth mentioning specifically.

  • Decongestants (e.g. xylometazoline nasal spray, pseudoephedrine)

These are commonly used in colds and flu to help unblock your nose. They can help with ear clearing and are sometimes used by divers for this purpose. If you are unable to equalise your ears at surface without medication you should not be diving.  Decongestants may cause a short-lived improvement which may wear off at depth and cause “reverse block”  barotrauma.

There is a theoretical risk that decongestants such as pseudoephedrine can lower the body’s threshold for undergoing a seizure and this must also be borne in mind.

  • Sea sickness tablets

If you need to take a sea sickness remedy for boat dives then unless these cause drowsiness it is safe to dive after taking these.

  • Hayfever tablets

Unless these cause drowsiness then it is safe to dive whilst taking hayfever medication. If your hayfever causes you to wheeze, you should not dive until this has settled.

Illegal drugs

Divers are told during training not to use illegal drugs but are given few facts about the risks that could affect their diving. A survey under our ‘Health of Divers’ research programme has enabled us to produce this downloadable leaflet – Diving and drugs.