Veganism is about being practical and causing the least possible harm.
Speak to your doctor or consultant about your concerns.
It is easier to avoid medicine that contains animal ingredients. Some of the items commonly found in medicines that are not vegan, include gelatine and lactose. There are some alternatives to these. Ask your doctor or pharmacist.
The development of medical research that does not use other animals is very promising. It is fair and it is also better science.