When you have a viral illness, such as a cold or flu, your upper respiratory system swells and becomes congested with mucus. Your eustachian tubes and sinuses may become blocked, causing difficulty with equalising your ears and sinuses.
What problems can this cause when diving?
If you’re not able to equalise your ears and sinuses properly, this may cause:
- Middle ear barotrauma- ear pain and hearing loss
- Inner ear barotrauma- ear pain, hearing loss, tinnitus, dizziness, nausea, vomiting
- Sinus barotrauma- facial pain, nose bleeds
This can happen on descent (squeeze) and ascent (reverse squeeze).
Barotrauma can be very serious and may result in permanent hearing loss. As frustrating as it is to cancel a dive, it may not be worth the risk if you’re not well enough.
What about if I take decongestants?
Decongestants make you feel a lot better when you have a cold. They help to reduce the mucus and swelling in your nasal and ear passages, meaning you can breathe more easily and possibly clear your ears without any problems. The issue here is that the effects may wear off at depth, so although you may descend easily, the congestion could have built up again while on the bottom. This puts you at risk of a reverse squeeze, as gas cannot escape, causing severe pain. In this case, you have no option but to ascend, despite the pain, and can cause serious barotrauma to your ears and sinuses.
If you cannot equalise on the surface without taking medication, do not dive.
It’s also worth remembering that some decongestants can make you feel anxious and increase your heart rate, as well as a possible risk of reducing seizure threshold. None of these are ideal in an underwater environment.
Can I dive with a very mild cold?
If you feel your symptoms are very minor, it may not be necessary to abort your dive. As a responsible adult this would be up to you to decide, and without seeing you and examining you, DDRC cannot accept responsibility for this.
If you make the decision that you are going to dive, ensure you descend very slowly, equalising frequently before you feel any pressure building up in your ears. Have a very low threshold for aborting the dive if you have any problems though, as it is not worth risking damage to your ears or sinuses.
On your ascent, there is still a risk of a reverse squeeze. Be sure to ascend slowly, allowing your ears and sinuses to equalise themselves. People tend to run in to problems here if their decongestants have worn off or they forced their equalisation on the way down.
If you do hurt your ears, don’t dive again until they’re fully healed and see a doctor in the meantime to check for any visible damage.
When should I definitely not dive with a cold/ flu?
- Inability to equalise ears at the surface without taking medication
- Inability to breathe through each nostril individually
- If you’ve had a fever/ temperature/ chills in the last 24 hours
- If you have blown your nose or coughed in the last 2 hours
- If you have a chesty cough
- If you don’t feel up to doing any other form of strenuous activity