Is It Safe To Give My Infant T-Minic For 20 Days, And Could It Cause Facial Bumps?

Hii, My 4 months old baby had cough from last month , doctor prescribed T - minic 0.5 ml twice a day. After a few days I stopped giving the same , but when he again started coughing, from last 20 days I have been giving him T- minic 0.5 ml twice in a day again . Is it dangerous now ?? He seems to be ok, just few small bumps are there on his face .