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Erectile dysfunction can occur if one or more of these requirements are not met. The following are causes of erectile dysfunction: Cheap cialis Erectile dysfunction (ED), also known as impotence, is the inability to get and maintain an erection that is sufficient for satisfactory sexual intercourse. best place to buy viagra online forum buy viagra online
Substance abuse: Marijuana, heroin, cocaine, methamphetamines, crystal meth, and alcohol abuse contribute to erectile dysfunction. Alcoholism, in addition to causing nerve damage, can lead to atrophy (shrinking) of the testicles and lower testosterone levels. A penile erection is the hydraulic effect of blood entering and being retained in sponge-like bodies within the penis. The process is often initiated as a result of sexual arousal, when signals are transmitted from the brain to nerves in the penis. Erectile dysfunction is indicated when an erection is difficult to produce. There are various circulatory causes, including alteration of the voltage-gated potassium channel, as in arsenic poisoning from drinking water. The most important organic causes are cardiovascular disease and diabetes, neurological problems (for example, trauma from prostatectomy surgery), hormonal insufficiencies (hypogonadism) and drug side effects. The device helps draw blood into the penis by applying negative pressure. This type of device is sometimes referred to as penis pump and may be used just prior to sexual intercourse. Several types of FDA approved vacuum therapy devices are available with a doctor's prescription. buy generic cialis online in canada buy cialis online
A recent study suggests an epidemiological association between chronic periodontitis (periodontal inflammation) and erectile dysfunction, similarly to the association between periodontitis and coronary heart diseases, and cerebrovascular diseases. In all the three conditions (erectile dysfunction, coronary heart disease and cerebrovascular diseases), despite the epidemiological association with periodontitis, no causative connection has proved yet. Cheap cialis In a study of mice, researchers "found a complex positive feedback loop in the penile nerves that triggers waves of nitric oxide to keep the penis erect," a release stated. After the initial release of nitric oxide, the nerve impulses that begin in the brain or from physical stimulation are sustained, thanks to a biochemical process called phosphorylation. This process ensures that nitric oxide continues to be released, maintaining the erections of both mice and men.