I have a rare medical condition (don't know name) but when I laugh too hard my muscles go into spasms and I colapse or fall to the ground, how do I tell my mates to try not to make me laugh so much. Ta muchly x

I think a direct approach works best. Otherwise why would they assume you have a problem almost nobody else has ever heard about.

Learn what the name of the condition is and how it causes the reaction that it does. Then you will be able to explain to your friends what is happening and why. You can also learn about other people with your condition and how they have coped.

Just saying don't make me laugh sounds like a dare or challenge. You need to be up front and sincere about the issue as you can be.

If need be, you might need a parent to explain to them what is going on so that they can understand you aren't playing a trick on them or trying to gain sympathy by making something up. Children don't always believe what a mate tells them. An adult may also be able to explain what they can do to help you if something happens.

If they intentionally try to make you collapse, then they aren't your friends. If they understand what is happening and try to help you then they are. Choose your friends carefully.