Family Practice Physicians have consistently depended on this almost ideal antibiotic for use in treating a wide variety of gram-positive and gram-negative bacterial infections including but not limited to Pneumonia, Pneumococcal Infections, upper-respiratory tract infections, scarlet fever, and meningitis. Penicillin G was the first penicillin available and remains a drug of choice for many infections. All forms of penicillin may be administered IM but vary in the length of onset and duration depending on the salts used in the preparation. Bicillin C-R and Bicillin L-A are two additional formulations of Penicillin G used in specific infections (i.e.) sexually transmitted diseases (STDs) that require a longer-acting antibiotic.