A "needle pusher" can refer to someone who is either involved with drug use or someone who is skilled in the use of needles, such as a nurse. However, there are other words that can be used as a synonym, depending on the context. For instance, one can use the word "injector" to refer to someone who is skilled or used to injections. "Hypodermic needle user," "needle addict," or "intravenous drug user" can be used for someone who is involved with drug use. Another alternative could be "acupuncturist," which is a practitioner skilled in using needles for medical purposes. Overall, there are different words that can be used as a synonym for "needle pusher," depending on the context and the connotation intended.