What are the causes of my chest and left arm to hurt when I take medicine?

See doctor or... There is not enough information in your question to answer. The best person to answer it is your primary doctor, who knows your whole medical story, your medications, your allergies (if any). Alternatively you could talk to a pharmacist to find out if the particular medicine has those side effects. Be sure to mention all of the medicines and supplements you take, as they can interact.