You know the old adage 'Buyer Beware'? Make sure you remember it when deciding whether to buy real Viagra, or to save a few bucks and buy a cheap knockoff.

A 47-year old Vietnamese man purchased a fake Viagra tablet from a friend for less than $2. Upon taking it that evening, he did indeed get the results he wanted. But, much to his dismay, the chemically induced erection wouldn't go away.

To make matters worse, the man didn't even have intercourse after taking the pill.

Two days after taking the pill, with his erection still 'firmly' intact, he was admitted to Binh Dan Hospital in Ho Chi Minh City.

Doctors performed a minor operation where they drained some blood from the man's erect penis in hopes to make his erection finally go down.