Can I go on a liveaboard with asthma, diabetes or on medication?

Often yes, with a dive-fitness assessment from a dive physician. Well-controlled asthma and diabetes are frequently cleared; you must declare them on the medical form.

Medical conditions are handled with a fitness-to-dive assessment rather than a blanket ban. Well-controlled asthma, diet or medication-controlled diabetes, treated hypertension and many other conditions are routinely cleared by dive physicians, provided they are stable and you have a signed medical statement.

How the process works: every operator asks you to complete a standard medical questionnaire before boarding. Answering yes to any item triggers a requirement for a physician's sign-off. Get this done at home, well before travel, ideally with a doctor trained in diving medicine — DAN maintains referral lists in most countries. Arriving at the boat with an unsigned form and a yes on the questionnaire can mean being turned away with no refund.

Practical planning on board: bring more medication than the trip length, split across two bags, keep it in original labelled packaging, and tell the cruise director what you take and where you keep it. Diabetics should discuss glucose management with the guides and carry fast sugar on the dive deck. Asthmatics should bring inhalers and store one in a dry box near the tanks.