Treatment depends on the cause. Testosterone supplements may be used for cases due to hormonal deficiency. However, the cause is more usually lack of adequate penile blood supply as a result of damage to inner walls of blood vessels. This damage is more frequent in older men, and often associated with disease, in particular diabetes.

Treatments (with the exception of testosterone supplementation, where effective) work on a temporary basis: they enable an erection to be attained and maintained long enough for intercourse, but do not permanently improve the underlying condition. There are different treatments available:

Oral treatment

3 different tablets are currently available from the doctor and these work when there is sexual stimulation. Depending on the treatment, it will need to be taken 20 minutes to 1 hour before sex and the period of time over which it works can vary between 3 hours and up to 36 hours.

Alprostadil

This can be injected into the penis or inserted using a special applicator - usually just before sexual intercourse.

BEFAR

Currently, only commercially available in the Far East, Befar® has shown a clinical efficacy of up to 83% in patients with varying degrees of ED. The cream itself has an onset action of 10-15 minutes and can continue on past 4-hours, and is favorably comparable to the efficacy of the injectable alprostadil.

Due to Befar’s direct application method (i.e. unlike Viagra®, Befar’s actions are limited to the area of its application), the side effects induced by the application have to date been limited to transient warm and burning sensations.

Vacuum pumps

These work by drawing blood into the penis and are also used just before sexual intercourse.

Hormone treatment

It is rare, but some men receive hormones for their erection problem. This does depend on the cause of the problem as well as other factors.

Surgery

Often, as a last resort if other treatments have failed, the most common procedure is prosthetic implants which involves the insertion of artificial rods into the penis.

Counselling

Counselling is often a consideration, both where a psychological cause is suspected or must be ruled out, or to assist in management of any distress.

ED can in many cases be treated by drugs taken orally, injected, or as penile suppositories. These drugs increase the efficacy of NO, which dilates the blood vessels of corpora cavernosa. When oral drugs or suppositories fail, injections into the erectile tissue of the penile shaft are extremely effective but occasionally cause priapism. When pharmacological methods fail, a purpose-designed external vacuum pump can be used to attain erection, with a separate compression ring fitted to the penis to maintain it. These pumps should be distinguished from other "penis pumps" (supplied without compression rings) which, rather than being used for temporary treatment of impotence, are claimed to increase penis length if used frequently, or vibrate as an aid to masturbation.

More drastically, inflatable or rigid penile implants may be fitted surgically. Implants are irreversible and costly.

All these mechanical methods are based on simple principles of hydraulics and mechanics and are quite reliable, but have their disadvantages.

In a few cases there is a vascular problem which can be treated surgically.

Uncontroversial treatments

PDE5 Inhibitors
The cyclic nucleotide phosphodiesterases constitute a group of enzymes that catalyse the hydrolysis of the cyclic nucleotides cyclic AMP and cyclic GMP. They exist in different molecular forms and are unevenly distributed throughout the body. These multiple forms or subtypes of phosphodiesterase were initially isolated from rat brain by Uzunov and Weiss in 1972 and were soon afterwards shown to be selectively inhibited by a variety of drugs in brain and other tissues. The potential for selective phosphodisterase inhibitors to be used as therapeutic agents was predicted as early as 1977 by Weiss and Hait. This prediction has now come to pass in a variety of fields, one of which is in the pharmacological treatment of erectile dysfunction.

One of the forms of phophodiesterase is termed PDE5. The prescription PDE5 inhibitors sildenafil (Viagra®), vardenafil (Levitra®) and tadalafil (Cialis®) are prescription drugs which are taken orally. They work by blocking the action of PDE5, which causes cGMP to degrade. CGMP specific phosphodiesterase type 5 causes the smooth muscle of the arteries in the penis to relax, allowing the corpus cavernosum to fill with blood.

(Specific devices are mentioned for information only; mention should not be taken as endorsement).

Dopamine Receptor Agonist

Inflatable implant

Rigid implant

Surgical treatment of certain cases

Controversial and unapproved treatments

Naltrexone
Drug used for treating drug addicts can have some success in patients with inhibited sexual desire.

Bremelanotide
The experimental drug bremelanotide (formerly PT-141) does not act on the vascular system like the former compounds but allegedly increases sexual desire and drive in males as well as females. It is applied as a nasal spray. Bremelanotide allegedly works by activating melanocortin receptors in the brain. It is currently in Phase IIb trials.

Melanotan II
Like bremelanotide the experimental drug Melanotan II does not act on the vascular system either but increases libido. Melanotan II works by activating melanocortin receptors in the brain.

hMaxi-K
hMaxi-K is a form of gene therapy using a plasmid vector that expresses the hSlo gene, that encodes the alpha-subunit of the Maxi-K channel. It has undergone phase I safety trials.

Ginseng
A double-blind study appears to show evidence that ginseng is better than placebo: see the ginseng article for more details.

Enzyte
Enzyte is a product that has been advertised by saturation coverage on television channels such as CourtTV. However, the Center for Science in the Public Interest (CSPI) has filed a complaint with the Federal Trade Commission (FTC) about Enzyte for deceptive advertising. It is manufactured by Berkeley Nutritionals, which is alleged to be the subject of an investigation by the Attorney General of Ohio and the defendant in class-action lawsuits.

Enzyte is a supplement that claims to increase the male libido or frequency of erections of the penis. Commercials for Enzyte are shown regularly on television. These commercials feature a man named Bob who never stops smiling, apparently because he had taken Enzyte and improved the size of his sex organs. The commercials are riddled with symbolic phallic imagery, e.g. golf clubs, remarkably tall glasses of iced tea, and a hose spraying barely a trickle of water (carried by someone who doesn't use Enzyte).

The effectiveness of Enzyte is in dispute. Some medical professionals in fact advise against taking Enzyte, saying that it can lead to damage. The Center for Science in the Public Interest have urged the Federal Trade Commission to disallow further television advertising for Enzyte due to a lack of proper studies supporting claims. Enzyte maker Berkeley Premium Nutraceuticals, Inc., is currently under a class action lawsuit for false advertising.

Enzyte is said to contain: Tribulus terrestris; Yohimbe Extract; Niacin; Epimedium; Avena sativa; zinc oxide; maca; Muira Pauma; Ginkgo biloba; L-Arginine; Saw Palmetto. Other ingredients: gelatin, rice bran, oat fiber, magnesium stearate, silicon dioxide.

Herbal and other alternative treatments
These are generally ineffective when tested blind, but may be useful for their psychological (placebo) effect: if a good result is expected, any highly praised, and often expensive, treatment can be effective. Reputable drugs can also benefit from the same effect. This is especially useful if blindfolded, as it helps to clear the mind of anxiety issues.

Prelox
Prelox is a Proprietary mix/combination of naturally occurring ingredients, L-arginine aspartate and Pycnogenol. In double blind tests carried out by Dr. Steven Lamm at New York University School of Medicine, 81.1% of men overall judged Prelox to be effective in improving their ability to engage in sexual activity. Prelox® for improvement of erectile function: A review European Bulletin of Drug Research, Volume 11, No. 3, 2003. Steven Lamm, Frank Schoenlau, Peter Rohdewald Whilst the supplements should be taken daily, the manufacturers claim that it brings the spontaneity back into ones' love life; unlike other products which must be remembered to be taken a fixed time before sexual activity.

Other treatment methods

Zinc

Zinc is known to help prevent the conversion of testosterone to estradiol, and testosterone is essential for proper erectile function and the synthesis of sperm (testosterone deficiency is a primary contributor in many cases of erectile dysfunction). Moreover, zinc levels have been found to be significantly reduced in both chronic bacterial prostatitis (CBP) and non-bacterial prostatitis (NBP). Many doctors and nutritionalists recommend zinc for prostate or erectile problems.

Zinc is best taken in lozenge form, as in tablet form the zinc is difficult to absorb, and can irritate the stomach lining.