Excellent advice, Charley. Antibiotics play havoc by killing all the 'good' natural digesting bugs in the gut. I was advised to take live yoghurt after two courses of very, very strong antibiotics to get rid of the giardia. If anyone goes abroad to Africa, India or places with dodgy hygiene/toilet facilities, any subsequent diarrhoea should be tested by the medical lab, as there is a long list of nasties, from parasites to dozens of tropical bacteria that might be having a lovely time in your tum!