How does Kamagra 100mg work?
The active ingredient in Kamagra is sildenafil citrate, which is a PDE5 (phosphodiesterase type 5) inhibitor. Erectile dysfunction occurs due to constriction of the arteries/blood vessels that restrict blood flow to the p*nis. Sildenafil citrate inhibits the PDE5 responsible for this constriction and, at the same time, increases the release of nitric oxide (NO), which causes dilation of blood vessels in the corpus cavernosum. 

Uses of Kamagra 100mg
It is used to treat the following conditions:Erectile dysfunction (ED or impotence): This is the inability to get or keep an erection strong enough to have s*xual intercourse.
Pulmonary arterial hypertension (PAH): a rare disease that affects the arteries of the lungs by increasing 
The recommended dose is one 100 mg Kamagra tablet per day. Do not consume more than one tablet within 24 hours. This medicine works best when taken on an empty stomach one hour before intercourse/s*x. It usually starts to work within an hour of taking it. But it may take more or less time dep*nding on a person's age, metabolism rate, and other medical conditions.

What happens if I miss a dose?
For erectile dysfunction, it should be taken when needed, so a person is unlikely to miss a dose. However, if you have been prescribed this medication to treat pulmonary arterial hypertension, take the missed dose as soon as you remember. Be sure to skip the next dose if it is to be taken within the next 24 hours. Never take a double dose.