In an insult to dietary supplement companies who at least try to play by the rules, a company has agreed with the US FDA to recall its product because it might work too well:
FDA and Ebek, Inc. notified healthcare professionals and consumers of a voluntary nationwide recall of the company’s dietary supplement because the product contains tadalafil, a drug used to treat erectile dysfunction.
Yes, you read correctly: if the herbal product doesn’t work, just add an actual prescription drug to the concoction. Tadalafil is better known in the US as Cialis. In fact, this adulteration of herbal “libido booster” supplements has shown up in the literature a few times already.
This is not dissimilar to the case of an herbal agent promoted for the treatment of prostate cancer, PC-SPES, that was withdrawn from the market because it contained two active estrogens, complicating the interpretation of a clinical trial that had been ongoing with the supplement.
Adulteration with prescription drugs is one of the lesser-known risks of using herbal medicines in our current regulatory climate. Dr Edzard Ernst of the Department of Complementary Medicine at the University of Exeter reviewed this issue in 2002 and found one report where 24% of supplements in Taiwan contained at least one conventional drug.
While late-night comedians may have fun with this story, this tadalafil adulteration case does carry potentially serious consequences. From the FDA press release this afternoon:
Tadalafil may interact with nitrates found in some prescription drugs and may lower blood pressure to dangerous levels. Consumers who have Liviro3 should stop using it immediately and contact their physician if they experience any problems that may be related to taking this product.