Adlarity From Corium

Indicated for the management of mild, moderate, and severe Alzheimer disease and dementia symptoms, the donepezil transdermal system (Adlarity; Corium) delivers donepezil hydrocholoride through the skin and is recommended at an initial dosage of 5 mg per day.

Pharmacology and Pharmacokinetics

The Adlarity patch is a rectangular laminate made of 6 layers: a tan overlay backing/adhesive, separating layer, drug matrix, microporous membrane, contact adhesive, and release liner (removed before application). Each patch lasts 7 days.

Donepezil enhances cholinergic function by increasing the concentration of acetylcholine through reversible inhibition of its hydrolysis by acetylcholinesterase. There is no evidence that donepezil alters the course of the underlying disease process.

Dose and Administration

The system can deliver 5 or 10 mg of donepezil daily for 7 days. At the end of the 1-week cycle, the used patch must be removed and a new patch applied. Only 1 transdermal system should be applied to the skin at any time.

The Adlarity system should be refrigerated. Before being opened, it should be allowed to reach room temperature without the use of external heat sources. Once opened, it should be immediately applied to clean, dry, healthy, and hairless (or nearly hairless) skin.

The recommended application site is the back but not across the spine. An area that will not be rubbed by tight clothing is best. The same application site should not be used for at least 2 cycles (14 days).

Clinical Trials

The FDA approved Adlarity in March 2022. Its efficacy was determined based on results of a relative bioavailability study of healthy individuals that compared transdermal donepezil with oral donepezil (Aricept).

Contraindications, Warnings, and Precautions

If a donepezil transdermal system falls off or a dose is missed, a new transdermal system should be applied immediately and replaced 7 days later to start a new 1-week cycle.

The most common adverse reactions to Adlarity are abdominal pain, abnormal dreams, constipation, diarrhea, dizziness, headaches, muscle spasms, skin tearing, sleeplessness, and irritation, itching, and pain at the application site.

The Adlarity system can cause allergic contact dermatitis and other application-site reactions, which should be monitored if they spread beyond the size of the transdermal patch and if symptoms do not improve within 48 hours after removal.

Because it is a cholinesterase inhibitor, the system is likely to emphasize succinylcholine-type muscle relaxation during anesthesia.

Cholinesterase inhibitors may have vagotonic effects on the atrioventricular and sinoatrial nodes, which can cause heart blockages in patients with—and without—known underlying cardiac conduction abnormalities. Cholinesterase inhibitors also cause increased secretion of gastric acid, which should be closely monitored for symptoms of active or occult gastrointestinal bleeding.

Based on results of previous studies, donepezil shows little or no evidence of direct inhibition of CYP2B6, CYP2C8, or CYP2C19 at clinically relevant concentrations. Whether donepezil has any potential for enzyme induction is not known. Formal pharmacokinetic studies evaluated the potential of donepezil for interaction with cimetidine, digoxin, ketoconazole, theophylline, and warfarin and observed no effects of donepezil on the pharmacokinetics of these drugs.

Reference

Adlarity. Prescribing information. Corium Inc. 2022. Accessed June 15, 2022. https://corium.com/ products/ADLARITY/ADLARITY_PI_ENGLISH_ US.pdf