There are a number of different types of medications that are prescribed to treat erectile dysfunction. These include:
Sildenafil (Viagra, Avigra, Dynafil, Revatio, Videna, Sildenafil Cipla)
The oral drug sildenafil, sold under the trade name Viagra, has been a media sensation. The blue diamond-shaped tablet takes about 60 minutes before sexual activity.
Sildenafil works by inhibiting an enzyme called 5-phosphodiesterase, thus increasing the levels of a substance called cyclic GMP. It is a powerful dilator of the blood vessels in the penis, which leads to influx of blood and an erection under stimulating circumstances.
There have been reports of Viagra users dying of heart attacks, but these attacks were not thought to be drug related. A certain percentage of heart attacks will occur during strenuous activity. However, manufacturers have issued warnings to people with cardiovascular disease.
Caution is specifically recommended for groups in which the drug has not yet been studied, such as men who have had a life-threatening heart attack, stroke, or arrhythmia in the last six months, those with significant hypotension (low blood pressure) Or hypertension (high blood pressure), those with unstable angina and those with retinitis pigmentosa, a disease that causes deterioration of the retina. The only current absolute contraindication is the concomitant use of cardiovascular drugs containing nitrates.
Nitrates such as glyceryl tri nitrate (GTN) or isosorbidemononitrate are generally prescribed for ischemic heart disease and angina.
Viagra has also become popular for recreational use, for example in nightclubs. However, it is a prescription drug that should only be taken under medical supervision.
Experts say it has no benefits for men who have normal erections. It can be lethal when used in conjunction with inhaled amyl nitrate (“poppers”), a recreational drug particularly popular with gay men.
It is used to create a “surge” of sexual stimulation, but in the process it also causes blood pressure to collapse to levels that can be dangerously low. This also applies to the use of Viagra along with nitrate-containing heart medicines.
Viagra costs between R70 and R100 a tablet, depending on its strength, but generic forms of the drug are also available.
After the phenomenal success of Viagra, several other drug companies have launched similar type of drugs. These include Vardenafil and Tadalafil.
Vardenafil or Levitra, like Viagra, is a type 5 phosphodiesterase inhibitor and was developed specifically for erectile dysfunction as an oral agent. Multiple trials have shown that Levitra is effective at improving the rate of achieving and maintaining an erection during intercourse. There was also improvement in other aspects of sexual function, including confidence, orgasmic function, and overall satisfaction.
Vardenafil produces significant improvements in erectile dysfunction, regardless of age, baseline severity and the cause of erectile dysfunction. It is also sometimes effective in patients with diabetes and after radical prostatectomy surgery for prostate cancer. Levitra has a rapid onset of action and sexual intercourse is possible as soon as 16 minutes after swallowing it.
Levitra is well tolerated with side effects very similar to that of Viagra. The most common side effects are headache, redness, rhinitis (nasal congestion) and indigestion (heartburn), which are mild or moderate and generally decrease with continued treatment.
Levitra comes in two doses ie ten and twenty milligrams. Ten milligrams is more than adequate for mild to moderate erectile dysfunction. It is also available in a 10 mg gold-dispersible, quick-action format called Levitra 10 mg ODT.
Tadalafil (Cialis, Ciavor)
Tadalafil is another drug used to treat erectile dysfunction. It has been termed the weekend drug for its long duration – up to 36 hours in some patients. This is because the chemical structure is different from the other two PDE-5 inhibitors. It has been shown to be effective for most causes of erectile dysfunction.
Side effects, although similar to the other two PDE-5 inhibitors, have the addition of back pain that appears to be self-limiting, mild, and benign. Cialis is also contraindicated with nitro-glycerin or any nitrate medication due to a drop in blood pressure.
A low dose concentration of Cialis (5 mg) is now available for daily use. Although expensive (over R800) it could be advantageous to regain erectile function after radical prostatectomy.
It should be noted that the three companies that manufacture Viagra, Levitra and Cialis published an exemption from liability in 2008. They affirmed that several cases of sudden hearing loss with these drugs had been reported. However, it does not seem to be a major problem.
More information about medication
– Other drugs claim to be effective but have not been proven in scientific studies. These include yohimbine hydrochloride, dopamine agonists and serotonin, as well as trazodone. These drugs are often mixed with alprostadil (a prostaglandin), to achieve better results.
– Medications can be used along with counseling, psychotherapy or psychiatric medication if erectile problems have psychological causes.
Reviewed by Dr Dave Bowden MBBCh (Wits), FCS (SA) Urol. Urologist Specialist in Private Practice, Christiaan Barnard Memorial Hospital, Cape Town.