A new patient to your base/post comes into your office since you are "on call". The patient is 'passing through' en route to their new PCS station. The mother asks that 'as long as they were there' if you'd refill their pemoline [Cylert®] for her son's attention deficit hyperactivity disorder (ADHD) so they wouldn't run out. You have no records, no medical history, and no labs. Mom says the patient (who's ADHD has been well-controlled without any apparent adverse events) hasn't been seen or had labs drawn since their last visit to their PCM almost 6 months ago. 

Do you refill the Cylert® or not? Why or why not?

NO!

First of all, pemoline is a controlled drug and should have an entry into the medical record each time a prescription is written. If this was a true emergency the answer may be different but since this is a 'convenience' refill, you'd probably be better off not writing the prescription. Since the drug is a stimulant, there is a potential for psychological and/or physical dependence

Secondly, (and probably even more important) is that pemoline has been associated with life-threatening hepatic failure. Since this patient has had NO labs drawn and reviewed in almost 6 months, to refill the prescription without lab monitoring is not advised.

Pemoline is a CNS stimulant (sympathomimetic). It's indicated for treatment of ADHD as part of a total treatment program. It is NOT a first line agent. Some unlabeled uses include narcolepsy, excessive daytime sedation, and fatigue in MS patients. It's been used as an adjunct for the treatment of depression in terminal cancer patients.

The Cylert® package insert contains a black box warning about the drug's association with life threatening hepatic failure. Since the drug marketing in 1975, 15 cases of acute hepatic failure have been reported to the FDA. Of the 15 cases reported as of Dec 98, 12 resulted in liver transplant or death, usually within 4 weeks of the onset of signs and symptoms of liver failure. The earliest onset of liver failure was 6 months after the start of drug therapy. Some cases reports include some non-specific prodromal symptoms (dark urine, malaise, anorexia, GI symptoms) before onset of jaundice. Other case reports did not.

Since adverse event reporting is voluntary and there's a long latency period between drug therapy initiation and occurrence of hepatic failure, it's likely that the number of cases is larger. The package labeling states the rate of reporting ranges from 4 to 17 times that expected in the general population.

The manufacturer recommends pemoline be used only in patients who have failed other first-line therapies and who do NOT have pre-existing liver disease (contraindication). A liver function monitoring program is recommended at baseline and EVERY TWO WEEKS thereafter. If the ALT (SGPT) increases to > or equal to two times the upper limit of normal, pemoline therapy should be discontinued esp since immediate withdrawal of the drug upon recognition of symptoms appears to enhance the likelihood of recovery.

The manufacturer also recommends WRITTEN INFORMED CONSENT from the patient and/or parent BEFORE starting pemoline therapy.