Hepatotoxicity upon using niacin to pass a drug test: A case report

To report a case of hepatotoxicity when niacin was used by a patient with HIV to pass a drug test.

Niacin is a soluble pyridine derivative widely used in the management of dyslipidemia. Common adverse effects include flushing, nausea, gastrointestinal discomfort, and hepatotoxicity. The use of niacin for nonmedical purposes has been increasing in prevalence in recent years, particularly in attempts to alter or mask results of urine drug tests. Although there is no scientific evidence that niacin can alter a urine drug screen result, easily retrievable information exists on the Internet touting niacin as a potential way to prevent detection of tetrahydrocannabinol (THC). The following report describes a case of hepatotoxicity in an HIV-infected adult who reported using niacin to mask THC in urine drug screen results.

The patient developed marked elevations in his liver enzymes (aspartate aminotransferase greater than 25 times the upper limit of normal and alanine aminotransferase greater than 3 times the upper limit of normal) that resolved after discontinuation of the drug. Because of the patient's self-reported use and discontinuation of niacin, the Naranjo Adverse Drug Reaction Probability Scale demonstrated a "definite" relationship between the development of hepatotoxicity and the ingestion of over-the-counter sustained-release niacin. The patient did not develop further clinical abnormalities proposed to be secondary to niacin toxicity in previously published case reports, including glucose abnormalities, coagulopathies, metabolic acidosis, QTc prolongation, and myalgias.

Health care providers should be aware of this nonmedical use of niacin to alter or mask a drug test, especially when discerning the cause of hepatotoxicity. In addition, pharmacists in the community setting should be aware of this use of niacin when encountering patients purchasing over-the-counter niacin, particularly in patients who may be more likely to use illicit substances.