What are four major health hazards when using narcotics?

narcotics are herion,opium,codeine,morphine,demerol,et... So, is there any health problems by using this narcotics?

not really that many if you use them short term and as directed by the doctor. a lot of prescription narcotics like codeine and hydrocodone contain acetominophen and addicts will take enough of them to damage their liver, especially after theyve built up a tolerance and need large doses to get a high. also, large doses and/or taking them with alcohol as a decent number of addicts do can cause neurological or breathing problems that can be potentially fatal. injection drug abusers are at risk for blood borne illnesses like hepatitis and HIV

Death is the only health hazard that's important enough.
Mother of B & D

you are talking about opiates here. And used under a doctor's supervision, there are no real major health hazards.
Used illegally, hazards include: respiratory failure leading to death, liver failure leading to slow death, destruction of brain cells also leading eventually to a drooling death, and cardiac failure leading to a quick but painful death.
Be aware, there are many other narcotics out there, and other risks associated with them.

None other than the fact that they COULD KILL YOU!
An overdose causes #1 respirations to drop drastically low which means no oxygen to your brain.
#2 Coma
#3 Nausea
#4 Addiction
Basically you could take them, come close to not breathing, lose consciousness, throw up in your mouth and not know it. If that doesn't kill you, get addicted and maybe next time it will.