Why is penicillin sometimes administered with Procaine?

Penicillin is often administered with Procaine to make the injection less painful. Procaine is a local anesthetic that helps reduce the discomfort associated with intramuscular injections. This is especially relevant because penicillin can be irritating to the tissues, leading to significant pain and discomfort for the patient during and after the injection. By combining it with Procaine, the needle insertion and the injection process become more tolerable, enhancing the overall patient experience and compliance with the treatment regimen.

While Procaine might have other potential effects, such as influencing the duration of medication action by slowing the absorption of penicillin into the bloodstream, the primary purpose in this context is to improve patient comfort during the administration of the penicillin.