Klonopin (rivotril, clonazepam) is a anti anxiety medication that is used to treat anxiety. It is available as a pills or a tablets form. Klonopin (rivotril, clonazepam) can be ordered without a prescription from many online pharmacies store. Before you buy klonopin online overnight, it is important to know the possible side effects of clonazepam (klonopin, rivotril) and whether it is good for you to take it.