Hi Thanks for posting your query on HCM I have read and understood your concern. Dark nail bed may not be related to your abdominal issues.Dark nail bed may be caused onchomycosis(nail fubgal infection) and is usually treated with anti-fungal agaents.However, your Doctor will have to examin the nail to confirm diagnosis. Abdominal bloating, flatulence, diarrhea... may be cuased by many medical conditions.Some possible causes may include: viral, bacterial or parasitic infections or may as well be due to food poisoning...I will suggest you try the following: -Take oral rehydration salt to replenish fluid and ions losses -If diarrhea too frequent, you take an anti-diarrheal agent like omodium If symptoms persist, you see the Doctor for a stool exam/culture and sensitivity test as a course of antibiotics may be needed. Hope this will help Wish you a speedy recovery. you may write back if more concerns Thanks Dr Mbuomboh