Diving with Crohn's Disease

by Peter Buzzacott

What is it ?

Crohn's Disease is a chronic inflammatory disorder of the gastrointestinal tract, the cause of which is still unclear. The disease may affect any part of the gastrointestinal tract from mouth to anus, is more common in women than men and most patients present at between the ages of 15 and 30 years. Although it can occur at any age diagnosis is rare before 10 years of age, however there is an increase in the number of children affected worldwide, some as young as 3 months old.. Many studies place the incidence of Crohn's Disease in western countries at between 2 and 6 per 100,000 population, with more than 400,000 Americans diagnosed with the disease, accounting for 76,000 hospitalizations per year. More than 10,000 Australians have Crohn's disease.

Signs and Symptoms

Signs and symptoms will vary from person to person and may flare up or recede at different times. In Crohn's disease some patients may exhibit the following symptoms: diarrhea (80%), weight loss (70%), anal lesions (65%), abdominal pain (55%), rectal bleeding (45%), fever (35%), fistula (similar to a weeping wound) (10%). Other features of the disorder may include: gallstones, malabsorbtion of food and nutritional deficiencies, weight loss or weight gain, eye complications like conjunctivitis, vomiting, pain, constipation, problems with joints and quite commonly mild abdominal distention and tenderness. Some people with Crohn's can experience a small gut obstruction and/or an abdominal mass.


Approximately 85% of patients with Crohn's disease require surgery during the natural course of their disease. Most sufferers can lead full and rewarding lives including sport diving during periods of symptom-stability, though more than half suffer recurrent attacks after the first surgical resection and half of this group will require further surgery. Currently there is no cure for this disease. Treatment is aimed at helping control the symptoms, though with the recent breakthrough in identifying the first gene in Crohn's, Nod2, there is hope of a cure as soon as 5 or 6 years time. (www.acca.net.au)


Patients may experience malabsorbtion problems and/or have nutritional deficiencies especially iron or folate and less commonly B12, complain of tiredness and/or weakness and may suffer weight loss or for some time there can be a weight-gain problem due to treatment, especially treatment with steroids. Those with diarrhea should take extra fluids to prevent dehydration, as should all divers, and they may find that it's best not to eat fruits, nuts, spicy or fatty foods just before long boat dives.

Resting the colon may reduce symptoms, for example special elemental liquid feeds are sometimes taken because they are so well absorbed that little residue reaches the colon. Anecdotal reports suggest that a dramatic reduction in refined sugar has reduced or alleviated some patients diarrhea though there is little evidence to support this course of action as a treatment. A balanced fiber diet, if tolerated, is recommended in most cases, though some patients may not be able to tolerate a lot of fiber especially if they have had surgery.

Anti Inflammatory Treatments

Anti inflammatory drugs play an important role in the treatment of Crohn's disease. They may be used in conjunction with nutrition supplements and/or surgery. At first many sufferers are treated with drugs containing mesalamine to help control inflammation, such as those containing sulfasalazine (some causes drowsiness - do not drive, and others may cause rash, itch, headaches and / or neuromuscular effects for some people). Other possible side effects of mesalamine include nausea, vomiting and diarrhea, all of which can contribute to dehydration.

Corticosteroids are also sometimes prescribed, as are immunomodulators which can take three to four months of treatment before the drugs become effective and again the side effects may include nausea, vomiting and diarrhea A recent new drug infusion treatment is the US Food and Drug Administration approved Infliximab (Remicade), also available in Australia since August 2000, which has assisted many people with fistulas. The healing process for these people has been dramatic providing better quality of life and reducing pain though, as with all treatments, everyone is different so for some patients it may cause hypersensitivity reactions including itching or stinging skin and, rarely, difficulty in breathing, chills and/or low blood pressure.

Antibiotics may also be prescribed for various reasons, including:

  • ciprofloxacin (possible CNS stimulation, impaired alertness, rash, and others)
  • metronidazole (possible psychiatric disturbances)
  • ampicillin (possible gastrointestinal upset and sensitivity phenomena)

Antidiarrheal medications may include:

  • diphenoxylate (may cause fluid depletion, dependence, CNS disturbances)
  • loperamide (possible fluid/electrolyte depletion)
  • codeine (may cause nausea, vomiting, dizziness, drowsiness).

Diving with Crohn's

Divers with Crohn's disease may continue diving, in fact I've met two in the last four years, (that I know about). Many divers do not consider the effects of their treatment in the context of their diving, either through ignorance or seasonal variations. For example once the weather turns cooler many divers put their gear away and their diet changes. It is possible for a diver to receive treatment for a variety of symptoms and to reach a period of stability in time for the next 'diving season' and to then return to diving with an altered predisposition to dehydration, skin rash, etc. Divers might also find that they are returning to diving after a prolonged break due to illness, and that they'll benefit from professional supervision until they are 'back in the saddle'.

Theoretically it is also possible for divers with Crohn's disease to initially attribute unusual physical complaints (for example nausea, sore joints or skin rash) to the Crohn's when in fact another cause may be responsible, such as DCI which can also produce these symptoms. I dived with a guy this year after he'd eaten a dodgy meat-pie and upon surfacing from 3.5 atmospheres (25m) he almost exploded with vomit. I suspect that he'd been feeling a touch queasy at the very start of the dive and put this down to the choppy surface conditions and that for the next 40 minutes (it was a multilevel dive) his gut was producing gas that didn't need expelling until he returned to the surface. By then he appeared to me to have probably two bar in his stomach. With Crohn's sufferers being sensitive to stomach complaints this is a potential hazard. I spent quite a while considering all the possible causes of this occurrence, including asking my buddy detailed questions about his dive profile, previous disposition to seasickness, current medication and or illnesses and more, before deciding that it was probably the dodgy pie.

In many countries the drugs used to treat diarrhea may be available 'over the counter' and, though it should be said that adverse reactions such as those described before in brackets are rare, it's not impossible to imagine a Crohn's sufferer going on a diving holiday, suffering a bout of 'Bali Belly' what with the change in food and climate, and taking medication for it without proper consultation with a physician. Some years ago I was on a diving holiday in Southern Turkey and after a night on the scotch and kebabs (not before a day's diving though) I thought I'd treat myself to a few Immodium, a commonly available loperamide caplet. I didn't visit the little boys room again for SEVEN days !! I still went diving though because at the time I felt, like many divers, that as long as I was physically 'up to it' then I'd be fine. Nowadays I am strictly a 'no drugs diver' and won't dive after taking even the mildest of nonprescription medications, be it for seasickness or whatever. I simply don't know enough about the possible effects to feel comfortable diving after I've taken anything.

Weight-loss sufferers, in particular those who rely on their semidry suits to stay warm, may find that when they return to diving after their symptoms subside that they have a fair amount of cold water sloshing about leading to excessive heat loss. As Crohn's is more common in women than men and 70% endure weight loss this scenario is not unlikely. For anyone who's susceptible to the cold anyway, for example women whom are also low in iron, semidry suits are worth the high price they cost, but then if they don't fit when the diver feels ready to return to the water then in many cases it will be unlikely that the diver will lash-out for another one straight away. More likely they'll endure until they can fill-it-out again meaning you could be in the water with someone wearing a semidry who'll be shivering well before you even feel mildly cold.

Dehydration is a major factor in susceptibility to decompression sickness and divers with Crohn's should take extra care to stay hydrated as they are more likely than the rest of us to deplete their hydro-reserves. Getting tired easily may mean that one-dive outings are better suited to divers with Crohn's, as opposed to three-dive day trips. And lastly, divers with Crohn's may need a little extra comfort for their, ahh, rear assets. It is common for divers with Crohn's to have sore butts, either from frequently visiting the restroom or open wounds or even anal bleeding. They won't dive with you again if you highlight this, and they won't enjoy rough weather on aluminum bench seats.

I do not know how nitrous and other mixed gases impact on Crohn's. Some arthritis suffering friends of mine are convinced that the elevated partial pressures of oxygen experienced during deep dives provide a full day's relief from joint pain and since joint pain is another symptom of Crohn's it is plausible that some symptom alleviation may occur though I've not yet heard of this either way.

My Next Dive

My next dive with a buddy with Crohn's, that I know of, will be on a charterboat called Dawnstar II, going to the fabulous Rottnest Island off Fremantle, Western Australia. I'll drive us the two hours north and my buddy knows that we'll leave early just in case he needs to stop a couple times on the way. The vessel has comfy seats and a walk-in toilet (the head), and a hot shower for pre-warming the semidry suit that now fits again after last years substantial and dramatic weight-loss. My buddy uses an integrated weight BCD because sometimes he'll feel 'a bit bloated' and so finds this better than a weightbelt. Lunch and a post-dive fruit platter are included in the price but my buddy will take his own food to reduce the chances of the day being spoilt by an upset tummy. My buddy knows that I hold no expectations that he'll dive on the day and so if, even at the last moment, he decides that he doesn't want to go in I won't even ask why. This is the rule in our dive club, anyone can call off any dive at any time without giving a reason. After the first dive there is a dim room below with comfy mattress-type cushions in case my buddy is tired and needs to rest, or in case he's a bit nauseated.

I will go out of my way to make the day as enjoyable as possible for my buddy with Crohn's. He's not taking any drugs and his doctor sees no reason why he shouldn't enjoy sport diving, in fact a low stress life is preferable and diving is as low stress as life gets. If any divers with Crohn's disease reading this want to comment they may send e-mail to me at reefdiving@eftel.net.au and in particular I'd be interested to hear about your diving experiences in relation to Crohn's disease. In conclusion, it is important for divers with Crohn's Disease to discuss their treatment with their physician prior to diving and to consider all the relevant factors before deciding to dive.

© Peter Buzzacott

Peter Buzzacott is rated by the Professional Association of Diving Instructors as a Master Instructor and he owns a Dive Shop in Bunbury Western Australia.