One of the greatest advances in sexual health for men was the creation of drugs to treat erectile dysfunction, allowing men who couldn't achieve an erection because of age, illness or injury, to resume sexual activity. Viagra, a drug famous for inspiring men to, well ... new heights, is one of the most popular medications of all time racking up sales of nearly $1.5 billion a year. It belongs to a class of drugs known as PDE-5 inhibitors. All drugs in this category -- which also includes Levitra and cialis -- allow the walls of the blood vessels in the penis to relax so that more blood flows through; with sexual stimulation, blood flow out of the penis decreases, and the result can be improved erectile function.
But like any medication, ED drugs may have side effects. Most reactions, such as congestion, stomach aches and headaches, are generally harmless and temporary. But in some cases, the drug works a little too well and the erection can go on for hours or even days. This may sound like every man's dream but according to Sandeep Grewal M.D., a physician with the ACE Medical Group in Rock Hill South Carolina, it's actually quite painful and can even lead to permanent muscle damage. "An erection that goes on and on is a condition known as priapism," he explains. "In rare instances the penis will turn black and the skin will peel away."
All three PDE-5 inhibitors have also been associated with compromised vision, in particular a condition known as non-arteritic ischemic optic neuropathy (NAION). Symptoms include sudden or partial blindness which usually occurs upon wakening. This is medical emergency that requires immediate attention.
About one in 200 men who take Viagra report blurry vision, a side effect that rarely occurs with Levitra or Cialis. Some Viagra users also experience blue or green tinted vision which can be permanent. Medical experts think this color disturbance may be because Viagra inhibits certain enzymes in the penis which also exist in the cone cells of the retina that are responsible for color vision. By blocking this hormone it also seems to block the perception of blue or green. Cindy Reilly, director of the practice development division for American Society of Health-System Pharmacists, notes this symptom can be predicted to some extent by examining the shape of the eye and the depth of the optic nerve -- something doctors rarely do before writing out a prescription.
LOSS OF HEARING
Another uncommon side effect involves disturbances in the ear. In fact, Viagra, Levitra and Cialis now include warnings about sudden hearing loss and informs patients that they should seek immediate medical attention if they experience a sudden loss or decrease in hearing. In the majority of the Viagra, Levitra and Cialis users who experienced this problem, the sudden hearing loss occurred within hours to two days of taking one of the drugs. In some of the cases, the sudden hearing loss was accompanied by ringing in the ears and dizziness. In many cases, the hearing loss was permanent.
On a happier note, one side effect of Viagra is a life saver.
Young children with a debilitating lung condition known as pulmonary arterial hypertension are being given the drug to lower pressure in their lungs, improving symptoms and slowing deterioration long enough until a lung transplant can be performed.
"For this use it's marketed under the name Revatio because parents do not want to hear their kids are taking Viagra," Grewal says.
Reilly is quick to point out that most of the weirder reactions to ED drugs are rare indeed, arising less than one percent of the time. "The take home message should be for users not to exceed the recommended dosage and if you notice something wrong, pick up the phone and call your doctor immediately."