Certain unauthorized natural health products marketed to treat erectile dysfunction contain undeclared pharmaceutical ingredients that should only be taken under medical supervision, Health Canada warns consumers.

Zimaxx, Actra-Rx, 4Everon, Vigor-25 and Nasutra could pose serious health risks for people with medical conditions, particularly if they are at risk for strokes and heart disease.

Use of these products could lead to sudden vision loss, increased heart rate, decreased blood pressure, penile tissue damage, permanent loss of potency, urinary tract infections, indigestion, headaches and dizziness.

The products can also cause a type of vision loss called nonarteritic anterior ischemic optic neuropathy in people over 50 and those with high blood pressure, high cholesterol, diabetes, smoking or blood vessel problems. The vision loss may be irreversible in extreme cases.

The products are not authorized for sale in Canada but may have been purchased online or brought into the country by travellers.

Consumers should stop using these products immediately and consult a health professional or Health Canada at (613) 957-2991, or toll free at 1-866-225-0709.

Health hazard alert