Three men with terrible addictions go and visit the doctor...
The alcoholic is the fist to enter - "Well", says the doctor "you have damaged your liver beyond repair - if you have one more drink, you will drop dead."
Shocked the man leaves, vowing never to drink again.

The doctor’s next patient is a heavy smoker - "Right", says the doctor, "your lungs are coated so heavily on tar that I’m affraid to say if you smoke one more cigarette, you will drop dead".
The man leaves, clearly shaken promising himself to never puff on a cigarette again.

The doctor’s final patient is a raging homosexual. "Well,I say", says the doctor, "I’m afraid that if you give in to your addiction just one more time, you will also drop dead".
The homosexual leaves, resigned to the fact he will never have sex again.

The 3 men are walking down the street when they pass a pub - the alsoholic can’t help himself and runs into the pub for his final sip of beer - he drops dead.

The 2 remaining men are shocked but continue their walk down the road where they come across a whole burning cigarette lying on the pavement. The smoker stops to admire it - shaking.

As he’s about to bend down and pick it up the homosexual turns to him and says "You do realise if you pick that up we’re both dead!"