I don't have an answer to your question, but thought I'd bring up a related point. You should be able to get most common
drugs (like ibuprofen), and many not-so-common ones, for dirt cheap over there. When I went to India in May, I gladly forgot
all my prescriptions at home . Luckily, I knew all the medicines, and managed to get them (well, the Indian brands) for
all of Rs 87/- (~ $2)!! This was in Leh, and from what I've heard, Kathmandu is a much bigger place than Leh. And yes, you can
just walk into most drug stores and get what you want (without a prescription) -- as long as you know what you want .