I have a perforated eardrum, and on descent in to an airport, I experience excruciating pain from the increase in air pressure. I have tried various methods to alleviate the problem - using an earplug, sucking a sweet, swallowing repeatedly and yawning - but all to no effect. The pain is so bad that I have started to dread flying. Is there anything I can do to prevent or reduce the pain?

Dr Jules Eden replies: This sounds a bit odd. If you have a hole in your eardrum, then as the plane descends air will contract in the middle ear, and air should be drawn into this space through the hole you have. So either the hole has closed, or there may be a one-way valve-like situation stopping air from being sucked in. You need to see your doctor again to check the current state of the eardrum. If the hole is still there, then never use an earplug as this will worsen the situation. Try using a tablet called Sudafed - this dilates the Eustachian tube and allows air to pass more easily into the middle ear. Finally, if this really ruins flights, and there are no contra-indications, then as a last resort, a grommet can be inserted. This is a plastic pipe placed across the drum that allows air to vent easily in and out of the middle ear. This, though, needs an ENT referral, which can take time.

I want to go scuba diving but have a non-functional arm and a severely damaged femoral vein in one leg, the result of DVT. Am I required to have a fit-to-dive certificate? If so, how do I get one? And does my friend who is in average health, need a certificate also? Is there someone I can contact to arrange the certification or can my own GP issue one?

Yes, you do need specific medical clearance to dive. In your case, you need to see someone who specialises in diving medicine in order to be passed fit. There will be issues with your arm, and how that limits certain diving actions, as well as any medications you may be taking after the DVT. If you are on warfarin, then there will be depth restrictions, and if you are not then it would be advisable to take an aspirin each day you dive. GPs should only be used to pass a diver as fit if there are no medical issues. However, your friend can see their doctor. For a list of how medical conditions affect diving together with details of a local dive doctor, visit e-med.co.uk. Click on the 'Diving Medicals' icon on the site and you will find the information you need.

· If you have any questions you want to ask Dr Jules Eden, email travel.doctor@theguardian.com, or write to The Flying Doctor, The Guardian, 119 Farringdon Road, London EC1R 3ER.