If your patient refuses or is unable to take oral medication, Invega Sustenna and Zyprexa Relprevv are potential alternatives (as is fluphenazine). Both Invega Sustenna and Zyprexa Relprevv begin acting right away, so no oral overlap is needed. Both medications are also conveniently packaged as pre-filled syringes; however, dosing can be a bit tricky. For example, Invega Sustenna requires two separate loading doses one week apart (234 mg on day one, and 156 mg on day eight). The maintenance dose, usually 117 mg (the equivalent of 6 mg oral), is given every four weeks (Bishara D, Neuropsychiatr Dis Treat 2010;6(1):561–572).