Allergy to Restylane
If you had an allergic reaction to Restylane I would advise against repeating Restylane for fear you will have an even worse reaction. All of the other fillers currently on the market are made of similar substances. Collagen and Cosmoderm are no longer on the market so there are no alternatives currently for you to try.
Allergic reaction to Restylane
if you had an allergic reaction that was verified or even strongly suspected then you should not use this product again. Unfortunately essentially everything that you could inject into your lips is what is referred to as a hyaluronic acid. This type of filler is really the only one well designed to augment lips. One of your other alternatives in this case would be a Silastic or silicone lip implant like the Permalip.
Best of luck