It depends on the antibiotic. Some affect the birth control in the intestine, Depo doesn't enter the intestine so these antibiotics won't have an effect on it. Others metabolize in the blood stream...
No, amoxicillin will not decrease the effectiveness of the Depo-Provera to prevent an unintended pregnancy. Since the Depo-Provera shot bypasses the absorption phase in the gastrointestinal tract...
No, but shingles are caused by a virus so you should not be using an antibiotic for this illness, unless you scratch the lesions causing a skin infection.
top of your bum you just have to lower your trousers a little bit... i think it can technically go in any large area of muscle but they seem to do it there... :) the plus is you dont have to see them...