Fast Five Quiz: Long-Acting Injectable Antipsychotics

Ravinder N. Bhalla, MD


August 19, 2021

The absorption rate of LAI antipsychotics is slower than that of oral antipsychotics. In some cases, this leads to reduced peak-to-trough plasma concentration differences, which may be associated with less adverse effects and may contribute to improved tolerability.

The pharmacokinetic profiles of LAI antipsychotics are very different from those of oral antipsychotics. With most LAI antipsychotics, a large proportion of the injected product initially stays in the injection area. As such, the absorption rate of LAI antipsychotics is slower than the elimination rate, resulting in "flip-flop" kinetics, in which the time to steady state is a function of absorption and the concentration at steady state is a function of elimination.

Absorption at the injection site can be influenced by patient factors, such as body weight, subcutaneous fat, and vascularity of the injection site, as well as by drug properties, including water solubility and the delivery vehicle.

Learn more about LAI antipsychotics.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.