For me Gingo biloba and Tianeptine(Stablon) is really effective. Tianeptine also protective for brain from the negative side effect of stress as far I know. Verapamil also effective for palpitaion.
No medicine actually helps overcoming shyness. At best, they help you feel less anxious, more focused, etc. The best way to improve shyness is to do things you're afraid to do, and improve on your social skills.
