impotence

(redirected from anti-impotence drug)
Also found in: Dictionary, Thesaurus, Legal, Encyclopedia.

Impotence

 

Definition

Impotence, often called erectile dysfunction, is the inability to achieve or maintain an erection long enough to engage in sexual intercourse.

Description

Under normal circumstances, when a man is sexually stimulated, his brain sends a message down the spinal cord and into the nerves of the penis. The nerve endings in the penis release chemical messengers, called neurotransmitters, that signal the corpora cavernosa (the two spongy rods of tissue that span the length of the penis) to relax and fill with blood. As they expand, the corpora cavernosa close off other veins that would normally drain blood from the penis. As the penis becomes engorged with blood, it enlarges and stiffens, causing an erection. Problems with blood vessels, nerves, or tissues of the penis can interfere with an erection.

Causes and symptoms

It is estimated that up to 20 million American men frequently suffer from impotence and that it strikes up to half of all men between the ages of 40 and 70. Doctors used to think that most cases of impotence were psychological in origin, but they now recognize that, at least in older men, physical causes may play a primary role in 60% or more of all cases. In men over the age of 60, the leading cause is atherosclerosis, or narrowing of the arteries, which can restrict the flow of blood to the penis. Injury or disease of the connective tissue, such as Peyronie's disease, may prevent the corpora cavernosa from completely expanding. Damage to the nerves of the penis, from certain types of surgery or neurological conditions, such as Parkinson's disease or multiple sclerosis, may also cause impotence. Men with diabetes are especially at risk for impotence because of their high risk of both atherosclerosis and a nerve disease called diabetic neuropathy.
Certain types of blood pressure medications, antiulcer drugs, antihistamines, tranquilizers (especially before intercourse), antifungals (hetoconazole), antipsychotics, antianxiety drugs, and antidepressants, known as selective serotonin reuptake inhibitors (SSRIs, including Prozac and Paxil), can interfere with erectile function. Smoking, excessive alcohol consumption, and illicit drug use may also contribute. In rare cases, low levels of the male hormone testosterone may contribute to erectile failure. Finally, psychological factors, such as stress, guilt, or anxiety, may also play a role, even when the impotence is primarily due to organic causes.

Diagnosis

The doctor also obtains a thorough medical history to find out about past pelvic surgery, diabetes, cardiovascular disease, kidney disease, and any medications the man may be taking. The physical examination should include a genital examination, a measurement of blood flow through the penis, hormone tests, and a glucose test for diabetes.
In some cases, nocturnal penile tumescence testing is performed to find out whether the man has erections while asleep. Healthy men usually have about four or five erections throughout the night. The man applies a device to the penis called a Rigiscan before going to bed at night, and the device can determine whether he has had erections. (If a man is able to have normal erections at night, this suggests a psychological cause for his impotence.)

Treatment

Years ago, the standard treatment for impotence was an implantable penile prosthesis or long-term psychotherapy. Although physical causes are now more readily diagnosed and treated, individual or marital counseling is still an effective treatment for impotence when emotional factors play a role. Fortunately, other approaches are now available to treat the physical causes of impotence.

Medications

The first line and by far the most common treatment today is with the prescription drug sildenafil citrate, sold under the brand name Viagra. An estimated 20 million prescriptions for the pill have been filled since it was approved by the FDA in March 1998. It is also the most effective treatment with a success rate of more than 60%. The drug boosts levels of a substance called cyclic GMP, which is responsible for widening the blood vessels of the penis. In clinical studies, Viagra produced headaches in 16% of men who took it, and other side effects included flushing, indigestion, and stuffy nose.
The primary drawback to Viagra, which works about an hour after it is taken, it that the FDA cautions men with heart disease or low blood pressure to be thoroughly examined by a physician before obtaining a prescription.
In the summer of 2002, two investigational drugs were announced to become available in the near future to also treat erectile dysfunction. Vardenafil and tadalafil both helped men who also had such conditions as diabetes, high blood pressure and benign prostatic hypertrophy. The drugs are awaiting final FDA approval.
Vardenafil and tadalafil belong to the same group of chemical compounds as sildenafil, namely phos-phodiesterase type 5 (PDE-5) inhibitors. Some men cannot benefit from sildenafil or the two newer PDE-5 inhibitors because they have low levels of nitric oxide. British investigators reported in late 2002 that three different types of compounds are being studied as possible medications for men with low levels of nitric oxide. They are Rho-kinase inhibitors, soluble guanylate cyclase activators, and nitric oxide-releasing PDE-5 inhibitors.
Other medications under investigation as treatments for impotence are topical agents. Topical means that they are applied externally to the skin rather than being injected or taken by mouth. If approved, these drugs would provide a noninvasive alternative for men who cannot take sildenafil or other oral medications for impotence.
Injection therapy involves injecting a substance into the penis to enhance blood flow and cause an erection. The Food and Drug Administration (FDA) approved a drug called alprostadil (Caverject) for this purpose in July of 1995. Alprostadil relaxes smooth muscle tissue to enhance blood flow into the penis. It must be injected shortly before intercourse. Another, similar drug that is sometimes used is papaverine—not yet been approved by the FDA for this use. Either drug may sometimes cause painful erections or priapism (uncomfortable, prolonged erections) that must be treated with a shot of epinephrine.
Alprostadil may also be administered into the urethral opening of the penis. In MUSE (medical urethral system for erection), the man inserts a thin tube the width of a vermicelli noodle into his urethral opening and presses down on a plunger to deliver a tiny pellet containing alprostadil into his penis. The drug takes about 10 minutes to work and the erection lasts about an hour. The main side effect is a sensation of pain and burning in the urethra, which can last about five to 15 minutes.

Mechanical and surgical treatments

Another approach is vacuum therapy. The man inserts his penis into a clear plastic cylinder and uses a pump to force air out of the cylinder. This forms a partial vacuum around the penis, which helps to draw blood into the corpora cavernosa. The man then places a special ring over the base of the penis to trap the blood inside it. The only side effect with this type of treatment is occasional bruising if the vacuum is left on too long.
Implantable penile prostheses are usually considered a last resort for treating impotence. They are implanted in the corpora cavernosa to make the penis rigid without the need for blood flow. The semirigid type of prosthesis consists of a pair of flexible silicone rods that can be bent up or down. This type of device has a low failure rate but, unfortunately, it causes the penis to always be erect, which can be difficult to conceal under clothing.
The inflatable type of device consists of cylinders that are implanted in the corpora cavernosa, a fluid reservoir implanted in the abdomen, and a pump placed in the scrotum. The man squeezes the pump to move fluid into the cylinders and cause them to become rigid. (He reverses the process by squeezing the pump again.) While these devices allow for intermittent erections, they have a slightly higher malfunction rate than the silicon rods.
Men can return to sexual activity six to eight weeks after implantation surgery. Since implants affect the corpora cavernosa, they permanently take away a man's ability to have a natural erection.
In rare cases, if narrowed or diseased veins are responsible for impotence, surgeons may reroute the blood flow into the corpus cavernosa or remove leaking vessels. However, the success rate with these procedures has been very low, and they are still considered experimental.

Gene therapy

A newer investigational approach to the treatment of erectile dysfunction is gene therapy. As of late 2002, several preclinical studies have shown promise, but none of the gene-based strategies so far have yet been tested for safety.

Alternative treatment

A number of herbs have been promoted for treating impotence. The most widely touted herbs for this purpose are Coryanthe yohimbe (available by prescription as yohimbine, with the trade name Yocon) and gingko (Gingko biloba), although neither has been conclusively shown to help the condition in controlled studies. In addition, gingko carries some risk of abnormal blood clotting and should be avoided by men taking blood thinners such as coumadin. Other herbs promoted for treating impotence include true unicorn root (Aletrius farinosa), saw palmetto (Serenoa repens), ginseng (Panax ginseng), and Siberian ginseng (Eleuthrococcus senticosus). Strychnos Nux vomica has been recommended, especially when impotence is caused by excessive alcohol, cigarettes, or dietary indiscretions, but it can be very toxic if taken improperly, so it should be used only under the strict supervision of a physician trained in its use.

Prognosis

With proper diagnosis, impotence can nearly always be treated or managed successfully. Unfortunately, fewer than 10% of impotent men seek treatment.

Prevention

There is no specific treatment to prevent impotence. Perhaps the most important measure is to maintain general good health and avoid atherosclerosis by exercising regularly, controlling weight, controlling hypertension and high cholesterol levels, and avoiding smoking. Avoiding excessive alcohol intake may also help.

Resources

Books

Beers, Mark H., MD, and Robert Berkow, MD, editors. "Erectile Dysfunction." Section 17, Chapter 220. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.
Miller, Lucinda G., and Wallace J. Murray, editors. Herbal Medicinals: A Clinician's Guide. Binghamton, N.Y.: Haworth Press, 1999.
Pelletier, Kenneth R., MD. The Best Alternative Medicine, Part II. "CAM Therapies for Specific Conditions: Impotence." New York: Simon & Schuster, 2002.

Periodicals

Campbell, Adam. "Soft Science: The Exclusive World on Which Sex Supplements may Help and Which Won't." Men's Health May 2002: 100.
Cellek, S., R. W. Rees, and J. Kalsi. "A Rho-Kinase Inhibitor, Soluble Guanylate Cyclase Activator and Nitric Oxide-Releasing PDE5 Inhibitor: Novel Approaches to Erectile Dysfunction." Expert Opinion on Investigational Drugs 11 (November 2002): 1563-1573.
Christ, G. J. "Gene Therapy for Erectile Dysfunction: Where Is It Going?" Current Opinion in Urology 12 (November 2002): 497-501.
Cowley, Geoffrey. "Looking Beyond Viagra." Newsweek April 24, 2000: 77.
Gresser, U., and C. H. Gleiter. "Erectile Dysfunction: Comparison of Efficacy and Side Effects of the PDE-5 Inhibitors Sildenafil, Vardenafil and Tadalafil—Review of the Literature." European Journal of Medical Research 7 (October 29, 2002): 435-446.
"Is Viagra Safe?" Internal Medicine Alert June 29, 2002: 90.
Norton, Patrice G.W. "Investigational Drugs in Erectile Dysfunction. (Vardenafil, Tadalafil)." Internal Medicine News June 1, 2002: 50.
Yap, R. L., and K. T. McVary. "Topical Agents and Erectile Dysfunction: Is There a Place?" Current Urology Reports 3 (December 2002): 471-476.
"Yohimbe Tree Bark: Herbal Viagra Better Gotten by Rx." Environmental Nutrition February 1999: 8.

Organizations

American Foundation for Urologic Disease. 1128 North Charles Street, Baltimore, MD 21201. (410) 468-1800.
American Urological Association (AUA). 1120 North Charles Street, Baltimore, MD 21201. (410) 727-1100. www.auanet.org.
Center for Biologics Evaluation and Research (CBER), U. S. Food and Drug Administration (FDA). 1401 Rockville Pike, Rockville, MD 20852-1448. (800) 835-4709 or (301) 827-1800. www.fda.gov/cber.
Impotence Institute of America, Impotents Anonymous. 10400 Little Patuxent Parkway, Suite 485, Columbia, MD 21044-3502. (800) 669-1603.
National Kidney and Urologic Diseases Information Clearinghouse. 3 Information Way, Bethesda, MD 20892-3580. (800) 891-5390.

Key terms

Alprostadil — A smooth muscle relaxant sometimes injected into the penis or applied to the urethral opening to treat impotence.
Atherosclerosis — A disorder in which plaques of cholesterol, lipids, and other debris build up on the inner walls of arteries, narrowing them.
Corpus cavernosum (plural, corpora cavernosa) — One of two rods of spongy tissue in the penis that become engorged with blood in order to produce an erection.
Gene therapy — A menthod of treating a disorder by replacing damaged or abnormal genes with normal ones. Some researchers think that gene therapy may offer a new way to treat impotence.
Neurotransmitters — Chemicals that modify or help transmit impulses between nerve synapses.
Papaverine — A smooth muscle relaxant sometimes injected into the penis as a treatment for impotence.
Peyronie's disease — A disease resulting from scarring of the corpus cavernosa, causing painful erections.
Topical — A type of medication that is applied to a specific and limited area of skin, and affects only the area to which it is applied.
Urethra — The small tube that drains urine from the bladder, as well as serving as a conduit for semen during ejaculation in men.
Viagra — Trade name of an orally administered drug for erectile failure first cleared for marketing in the United States in March 1998. Its generic name is sildenafil citrate.

impotence

 [im´po-tens]
inability of the male to achieve or maintain an erection of sufficient rigidity to perform sexual intercourse successfully. An impotent man may produce sufficient numbers of normal spermatozoa; the condition is related to infertility only insofar as it prevents coitus with and impregnation of the female partner. Called also erectile dysfunction. adj., adj im´potent.
Etiology. Causes of impotence are usually classified as either physiological (organic impotence) or psychological (psychogenic impotence, officially called male erectile disorder).
Organic Impotence. Diabetes mellitus, thyroid disease, and dysfunction of the pituitary gland or testes can cause impotence, as can certain medications. Other organic causes include arterial ischemia associated with atherosclerosis of the aorta and common iliac arteries, extensive pelvic surgery such as radical prostatectomy, spinal cord injury and other neurologic disorders, and a history of cigarette smoking. Because certain medications can cause impotence, it is recommended that in cases of recent impotence it be determined whether the patient has started on a new drug. The most common offenders are diuretics, antihypertensives, and vasodilators. Alcohol, which sometimes is ignored as a drug, is often a contributor to the problem of impotence.

Occasional successful sexual function and early morning erections do not preclude the possibility of endocrine dysfunction. Since abnormally low levels of testosterone frequently are the primary cause of impotence, it is recommended that determination of the blood level of testosterone be an integral part of the total evaluation of the impotent patient.
Psychogenic Impotence. In the past, psychological factors were frequently listed as the most common cause of impotence. However, research has now demonstrated that physical factors are actually more common than psychological ones.
Treatment. prostatitis or another acute infection affecting the genitalia can cause temporary impotence that clears up in response to antibiotics. The smooth muscle relaxant sildenafil (viagra) was introduced in 1998 as a treatment for organic impotence. Administration of testosterone may be indicated if low levels of this hormone are found in a blood sample. If impotence is organic and does not respond to other therapies, a penile prosthesis can be implanted; this is usually done surgically by a urologist. Other therapies include the use of vacuum tumescence devices and penile injection of pharmacologic agents that cause dilation.
organic impotence impotence that has a physiological origin. See impotence.
psychogenic impotence (psychological impotence) impotence that has an emotional or psychological cause; called also male erectile disorder. See impotence.

im·po·tence

, impotency (im'pŏ-tens, -ten-sē),
1. Weakness; lack of power.
2. Specifically, inability of the male to achieve or maintain penile erection and thus engage in copulation; a manifestation of neurologic, vascular, or psychological dysfunction.
[L. impotentia, inability, fr. in- neg. + potentia, power]

impotence

/im·po·tence/ (im´po-tens)
1. lack of power.
2. specifically, lack of copulative power in the male due to failure to initiate an erection or maintain an erection until ejaculation; usually considered to be due to a physical disorder (organic i.) or an underlying psychological condition (psychogenic i., usually called male erectile disorder) .

impotence

(ĭm′pə-təns) also

impotency

(-tən-sē)
n.
1. The quality or condition of being impotent.

impotence

[im′pətəns]
Etymology: L, im, not, potentia, power
1 weakness.
2 inability of the adult male to achieve or sustain a penile erection or, less commonly, to ejaculate after achieving an erection. Several forms are recognized. Functional impotence has a psychological basis. Organic impotence includes vasculogenic, neurogenic, endocrinic, and anatomical factors. Anatomical impotence results from physically defective genitalia. Atonic impotence involves disturbed neuromuscular function. Poor health, old or advancing age, drugs, smoking, trauma, and fatigue can induce impotence. Also called erectile dysfunction, impotency. impotent, adj.

impotence

Ejaculatory incompetence, erectile difficulty, erectile dysfunction, erectile failure, frigidity–female Medtalk The inability to achieve or maintain a penile erection adequate for the successful completion of intercourse, terminating in ejaculation; penile erection is mediated by nitric oxide Epidemiology Prevalence of minimal, moderate, and complete impotence in the Massachusetts Male Aging Study was 52%; age is the most important factor; complete impotence ↑ from 5%–age 40 to 15%–age 70; for an erection to achieve a successful outcome, it requires
1. An intact CNS, ie without underlying medical or psychological disease, or central-acting drugs, intact sympathetic and parasympathetic circuitry, ie without spinal trauma or degenerative disease.
2. An intact vascular supply to the penis and.
3. An intact, anatomically correct penis; 25% of impotence may be psychologic or 'partner-specific', 25% has an organic component and 50% of impotence is organic in nature; in organic impotence, nocturnal penile tumescence is absent Management-surgical Microvascular surgery to bypass occluded vessels–most effective in younger ♂, penile prosthesis Management-medical Combined therapy with phentolamine and papaverine–self-injected by the Pt, wielding an erection of 1 hr's duration is useful for arterial, neurologic, psychogenic impotence; other therapies–zinc, bromocriptine–Parlodel, isoxsuprine-Vasodilan, Voxsuprine, nitroglycerine, yohimbine–Yocon, Yohimex Etiology Smoking, CAD, HTN, DM, medications–hypoglycemic agents, vasodilators, cardiac drugs, antihypertensives, anger and depression; it is inversely correlated to dehydroepiandrosterone, HDL-C, and an index of dominant personality Primary impotence Complete absence of successful sexual coupling Secondary impotence Priapism, penile plaques, Peyronie's disease; drugs linked to impotence: antihypertensives–eg, methyldopa, guanethidine, reserpine, clonidine, due to ↓ BP, antidepressants–eg, phenelzine, isocarboxazide, amitriptyline–causing altered moods and decreased libido, tranquilizers–eg, chlordiazepoxide and lorazepam, and the muscle-relaxing diazepam, cimetidine, which ↑ prolactin, and is associated with impotence and loss of libido. Cf Infertility, Orgasmic dysfunction.

im·po·tence

, impotency (im'pŏ-tĕns, -tĕn-sē)
1. Weakness; lack of power.
2. Inability of the male to achieve and/or maintain penile erection and thus engage in copulation; a manifestation of neurologic, vascular, or psychological dysfunction.
[L. impotentia, inability, fr. in- neg. + potentia, power]

impotence

The inability to achieve or sustain a sufficiently firm penile erection (tumescence) to allow normal vaginal sexual intercourse. The great majority of cases are not caused by organic disease and most men experience occasional periods of impotence. It is often related to anxiety about performance and is usually readily corrected by simple counselling methods which prescribe sensual massage but forbid coitus. Organic impotence may be caused by DIABETES, MULTIPLE SCLEROSIS, spinal cord disorders and heart disease. Many cases can be helped by the drug SILDENAFIL (Viagra).

impotence (imˑ·p·tns),

n poor sexual function and reproduction in the male, including erectile dysfunction, in which erection of the penis cannot be achieved or maintained.

impotence

inability of the male to achieve or maintain an erection of sufficient rigidity to perform sexual intercourse successfully.

Patient discussion about impotence

Q. I started to suffer from erectile dysfunction? Why is this happening and what can I do to treat it? I am a healthy 52 year old. I have hypertension but i take pills to treat it and my levels are around 130/80. except that I am at great shape. In the last few months I feel that a problem in my sex life. I want to have sex but i can't due to erectile dysfunction. What can be the reason for this? and more important what can I do?

A. get rize2 it lasts about 4 days,and all you have to do is think about sex
and you get a rock hard erection!!!!!

More discussions about impotence
References in periodicals archive ?
The anti-impotence drug Viagra(TM) works by stimulating local production of nitric oxide.
But as soon as we mentioned we wanted a large quantity of the anti-impotence drug, his eyes lit up and he said: 'I can help you but I need to get to know you first.
Scientists have carried out experiments which indicate that the anti-impotence drug can damage sperm.
The doctor refused to prescribe the anti-impotence drug Viagra and instead told him that a stable relationship, trust and patience was what he needed most.
Hopes that Viagra would do for women what it does for men were dashed in the first big study of the anti-impotence drug in females.
27 Kyodo The Fair Trade Commission (FTC) has raided the office of the Sakai Pharmacists Society in Sakai, Osaka Prefecture on suspicion of setting a sales price for the anti-impotence drug Viagra in violation of the Antimonopoly Law, society sources said Wednesday.
TOKYO, March 9 Kyodo The Health and Welfare Ministry said Tuesday consumers will have to pay the full price without the benefit of health insurance support for Viagra, an anti-impotence drug posting phenomenal sales around the world, which will soon be sold in Japan.
THE Royal family may not be amused, but this week their former yacht Britannia will play host to a promotional launch of the anti-impotence drug Viagra.
Among other things, Ignarro's research led to the development of the anti-impotence drug Viagra.
NEW YORK--(BW HealthWire)--July 16, 1998--The nation's first lawsuit seeking insurance coverage for the anti-impotence drug Viagra will come before a judge for the first time on Monday, July 20, in U.
London, July 1 (AN): Despite being given just a few weeks to live by doctors, a little boy with a serious heart condition has managed to survive, courtesy anti-impotence drug Viagra.
ANTI-IMPOTENCE drug Viagra can also help your heart, it was claimed yesterday.