Massage of injection site pre-injection:
Historically, there has been practice that included massaging the muscle area overlying the injection site before administering an intramuscular injection. This is said to relax the muscle prior to injection. This may or may not be helpful prior to the administration of long-acting injectable antipsychotic (LAI) medications. Some research on massage, conducted specifically with fluphenazine decanoate suggests that this maneuver leads to a delay in the drug’s absorption for up to an hour due to transient vasoconstriction (Soni, Wiles, Schiff, & Bamrah, 1988). This could not only delay absorption but alter the amount of drug entering systemic circulation, yet it is unlikely to make a clinically significant impact.
Massage of injection site post-injection:
For post-injection care, all evidence directs that clinicians should not massage the injection site. This may be particularly problematic for injections administered utilizing Z-track administration. Both of the first-generation/typical antipsychotics available in LAI formulation, haloperidol (Haldol Decanoate) and fluphenazine (Prolixin Decanoate), require a Z-track administration (per FDA prescribing information), which consists of pulling the subcutaneous layers of the skin out of alignment with the muscles to break the junction of each layer. This allows the medication to be trapped in place within the muscle post-injection. With Z-track technique, it is recommended that clinicians do not massage the area after injection (East, Maroney, & Liu, 2014). For any LAI antipsychotic injections given using the Z-track technique, massage of the injection site after the injection can inadvertently promote dispersal into the subcutaneous fatty tissue instead of into the muscle as intended (Haste, 2018). Many clinicians use the Z-track method for many or all intramuscular injections.
Some guidance is available specific to second-generation/atypical antipsychotics about injection site massage as well. Prescribing directions for paliperidone LAIs (Invega Sustenna and Invega Trinza) state that clinicians should avoid massaging or rubbing the injection site, as such may cause the product to breakdown and enter the bloodstream too quickly (Canterbury District Health Board, 2019). Although most antipsychotic LAIs are given intramuscularly, there is a new formulation of risperidone (Perseris), which is administered subcutaneously. Following a Perseris injection, patients should be advised that they will have a lump at the injection site which will decrease and disappear over time. They should not rub or massage the injection site or allow belts or waistbands to tightly constrict the area (Karas, Burdge, & Rey, 2019).
For all LAIs given intramuscularly, time to peak levels should be considered when avoiding any disruption to the post-injection site by rubbing or massage, as such is contraindicated. Generally, rubbing or massaging the injection site area should be avoided through the time the drug is expected to reach peak levels to avoid intended absorption patterns. These peak effect levels of antipsychotic LAIs can range from 2-4 hours (for olanzapine LAI [Zyprexa Relprevv]) to 44-50 (for aripiprazole lauroxil [Aristada]; Raoufinia et al., 2017), and details about each drug’s time to peak (Tmax) can be found in the individual drug’s FDA prescribing information.