Quality of extemporaneously compounded nitroglycerin ointment.
OBJECTIVE
Published clinical trials support the use of 0.2 to 0.4 percent nitroglycerin ointment for the treatment of an anal fissure, although no product is yet available in the United States. In 2004, 84,000 prescriptions were written for compounded nitroglycerin ointment. This study was designed to evaluate the quality of extemporaneously compounded nitroglycerin ointment.


METHODS
Prescriptions for 0.3 percent nitroglycerin ointment were filled at retail pharmacies and shipped to analytical laboratory for analysis by their validated method.


RESULTS
Five of 24 (20.8 percent) samples did not meet the United States Pharmacopoeia requirement for content uniformity of 90 to 110 percent and< 6 percent relative standard deviation. Seven of 24 samples (29.2 percent) were subpotent based on the United States Pharmacopoeia requirement of 90 to 115 percent of label claim, and 1 sample was suprapotent. When considered for potency and/or content uniformity, 11 of 24 (45.8 percent) were misbranded and poor quality.


CONCLUSIONS
Forty-six percent of the nitroglycerin ointment products compounded by 24 pharmacies did not meet the United States Pharmacopoeia specifications for potency and/or content uniformity when filling a prescription for 0.3 percent nitroglycerin ointment. These results raise significant issues regarding whether patients are put at undue risk relative to the relief of anal fissure pain. The pain associated with chronic anal fissure is severe, often debilitating, and may affect the patient's ability to work.
Azarnoff
Daniel L
DL
D.L. Azarnoff Associates, LLC, Burlingame, California 94010-2011, USA. dan@azarnoffassociates.com
Lee
J C
JC
Lee
Charles
C
Chandler
John
J
Karlin
David
D
D004339:Drug Compounding / Q000592:standards*; D004340:Drug Contamination; D004348:Drug Labeling; D006801:Humans; D005996:Nitroglycerin / Q000592:standards*; D009823:Ointment Bases; D010602:Pharmacopoeias as Topic; D019984:Quality Indicators, Health Care; D014481:United States; D014665:Vasodilator Agents / Q000592:standards*
D009823:Ointment Bases; D014665:Vasodilator Agents; D005996:Nitroglycerin