Long-acting injectable antipsychotics: What to do about missed doses
Use a stepwise approach based on the unique properties of the specific medication.
Second-generation LAIAs
Six second-generation LAIAs are available in the United States. Compared with the first-generation LAIAs, second-generation LAIAs have more extensive guidance on how to address missed doses.
Risperidone long-acting injection. When addressing missed doses of risperidone long-acting injection, first determine whether the medication has reached steady state. Steady state occurs approximately after the fourth consecutive injection (approximately 2 months).29
If a patient missed a dose but has not reached steady state, he or she should receive the next dose as well as oral antipsychotic supplementation for 3 weeks.30 If the patient has reached steady state and if it has been ≤6 weeks since the last injection, give the next injection as soon as possible. However, if steady state has been reached and it has been >6 weeks since the last injection, give the next injection, along with 3 weeks of oral antipsychotic supplementation (Figure 3).
Paliperidone palmitate monthly long-acting injection. Once the initiation dosing phase of paliperidone palmitate monthly long-acting injection (PP1M) is completed, the maintenance dose is administered every 4 weeks. When addressing missed doses of PP1M, first determine whether the patient is in the initiation or maintenance dosing phase.31
Initiation phase. Patients are in the initiation dosing phase during the first 2 injections of PP1M. During the initiation phase, the patient first receives 234 mg and then 156 mg 1 week later, both in the deltoid muscle. One month later, the patient receives a maintenance dose of PP1M (in the deltoid or gluteal muscle). The second initiation injection may be given 4 days before or after the scheduled administration date. The initiation doses should be adjusted in patients with mild renal function (creatinine clearance 50 to 80 mL/min).31 Figure 4 summarizes the guidance for addressing a missed or delayed second injection during the initiation phase.
Continue to: Maintenance phase
