Is it good to use sildenafil viagra ?

I am not feeling that much sexually excited these days. I don’t know what has happened as I don’t have any kind of health related problem. I went for check up in a nearby hospital but after having treatment for ten days; the situation is all the same. I am very much depressed and not finding any way out. My friend, who works with me in a company was suggesting that I should have sildenafil Viagra. But I am little skeptical as I am afraid it will have any side effects on me. Could you clear the confusion please?