The FDA is warning consumers to think twice before using “herbal” sex booster capsules.

Man Up Now capsules, which are being marketed as a dietary supplement for sexual enhancement, contain a variation of an active drug ingredient found in Viagra. According to the FDA, it can dangerously lower blood pressure.

The capsules are the latest in a string of the so-called “natural” sexual enhancement products to receive FDA scrutiny over the last few years, the organization says. Products that contain prescription-strength drugs while being marketed as “herbal” or “all natural” expose consumers to the potential for death or injury via unpredictable risks.

According to its release, Man Up Now is distributed by Synergy Distribution LLC and sold on online marketplaces, Internet sites and possibly in retail outlets. The product is sold in single, double, and triple blister packs, and in six-, 12-, and 30-count capsule bottles, the FDA says.

The FDA is advising those who have experienced negative side effects from sexual enhancement products to discard the product and consult a health care professional.

Juliana Keeping is a health and environment reporter for AnnArbor.com. Reach her at julianakeeping@annarbor.com or 734-623-2528. Follow Juliana Keeping on Twitter