Kamagra is an Indian brand name for a compound that treats erectile dysfunction, sildenafil citrate. Sildenafil citrate is more famously known as Viagra-the brand name given sildenafil citrate by its original patent holder, Pfizer. Manufactured by Ajanta Pharma, Kamagra is the Indian brand name for sildenafil citrate. Kamagra, along with other Indian-branded versions of sildenafil nitrate are collectively known as 'generic viagra' in India. Other Indian-branded sildenafil nitrate formulations include Zenegra, Penegra, Edegra, and Silagra.
Sildenafil citrate is used primarily for the treatment of erectile dysfunction (previously known as 'impotence') and, to a lesser degree, pulmonary arterial hypertension.
Also known as impotence, erectile dysfunction is a condition where the male penis cannot achieve erection or stay erect even when the male is sexually aroused, to the point of ejaculation. ED is caused by a wide variety of causes. The most common reasons for ED are: mental stress, nerve damage in the penis, damaged nerves leading to the penis, blood vessel damage, and muscle damage. Erection involves many different elements and ED occurs when any of the components required in the process become damaged, suffer stress, or undergo deterioration. There are two general categories of causes for ED: physical and mental.
Here are just some of the causes of ED which involve the physical body, its processes, and/or its functions. This is not an exhaustive list by any means-it only lists the most commonly identified physical reasons for erectile dysfunction.
To fully understand ED and how sildenafil citrate helps facilitate erections, we have to look at how an erection occurs. It all starts with impulses from the brain. The brain reacts to stimuli it perceives through the senses and sends chemical signals to the penis' muscles. However, if certain chemical compounds are degraded in the penis' tissues, erection is either very weak or doesn't happen at all. The key chemical compound required to produce an erection is cyclic guanosine monophosphate (cGMP). These molecules are suppressed or inhibited normally by the enzyme compound cGMP-specific phosphodiesterase type 5 (PDE5). This is why men aren't normally walking around fully erect. In the penis' normal state, PDE5 suppresses the action of cGMP. When a person has ED, PDE5's suppression of cGMP is sustained even when the person is sexually aroused mentally. When PDE5 is suppressed, the nitric oxide (NO) located in the penis' corpus cavernosum binds to molecular guanylate cyclase receptors. This results in elevated cGMP levels. Once a certain cGMP level is reached, the penis' muscles relax leading to increased blood flow into the penis' spongy muscle tissue. Once this spongy tissue fills up with blood, a full erection is achieved.
As mentioned above PDE5 suppresses cGMP levels. PDE5 is specific to the penis' muscles and parts of the heart. Sildenafil citrate inhibits or suppresses PDE5 from doing what it normally does-reducing cGMP levels. Since there is nothing suppressing cGMP levels, more blood follows to the arteries feeding the penis and erections are more likely. Keep in mind that sildenafil citrate does not produce sexual arousal. It merely ensures that blood flows to the areas where it should be flowing to produce an erection. The male must still be sexually aroused in order to achieve an erection. To this extent, sildenafil citrate can handle the physical barriers to erections but it cannot fix any psychological barriers to stimulation. Sexual stimulation is important because it boosts the nitrous oxide level in the blood coursing through the penis. Paired with the right cGMP levels, the nitrous oxide will dilate the blood vessels and allow blood to fill up the penis' spongy tissue resulting in an erection or a more durable erection. Sildenafil does not boost the nitrous oxide or cGMP levels. Stimulation does. Normally, stimulation is triggered by visual or sensory stimuli.
Sildenafil citrate's chemical structure looks very similar to cGMP. Remember, ED results when PDE5 binds to cGMP instead of nitrous oxide. Blood flow increase and blood vessel dilation only occurs when the muscles smoothen due to nitrous oxide interacting with cGMP. PDE5 prevents the binding of nitrous oxide and cGMP by binding to cGMP. Sildenafil nitrate is structured so similarly to cGMP that, when introduced to the blood stream, PDE5 binds to it instead of cGMP. Since it 'soaks up' PDE5, the PDE5 can't bind to cGMP like it does normally. As a result, cGMP and nitrous oxide are left free to bind and erections, assuming the proper level of brain stimulation and sexual arousal are present, are strengthened or achieved.
Kamagra, Viagra, and other brands of sildenafil citrate have the following side effects: blurry vision, vision impairment, congested nasal passages, mild stomach upset, flushing, and headache. In a small number of cases, sildenafil citrate users report that their vision has a temporary blue tint. Other small groups of sildenafil citrate users report that they lose their peripheral vision. In very rare cases, sildenafil citrate has been reported to cause nonarteritic anterior ischemic optic neuropathy which can be fatal. Other rare side effects include painful erections, heart attacks, extremely low blood pressure, hearing loss, and other conditions related to low blood pressure.
If you are taking any protease inhibitors to treat HIV, be very careful of taking sildenafil citrate because protease inhibitors decrease the metabolization of sildenafil. This results in elevated sildenafil plasma levels and increases the likelihood and severity of sildenafil's side effects. You should limit your dosage of sildenafil when taking protease inhibitors and space out your usage of this ED medication. The same effect has been observed in cimetidine and erythromycin.
Avoid taking sildenafil citrate with nitric oxide boosters, nitrates, or nitrites like nitroglycerin, amyl nitrite, and sodium nitroprusside.