Steroid injections are thought to be most beneficial within the first month of developing an alopecia areata patch. It is also possible that by controlling inflammation early on, the immune system is calmed and does not cause patches of hair loss elsewhere on the scalp, though this has not been proven. Steroid injections, on the other hand, can be administered at any time, according to your doctor’s recommendations, even one or two years after the presence of a patch.