Naltrexone is an opioid receptor antagonist used primarily in the management of alcohol dependence and opioid dependence. It is marketed in generic form as its hydrochloride salt, naltrexone hydrochloride.

This medication must be used under close medical supervision. Take this as directed. Do not increase your dose, take this more often or stop taking this without first consulting your doctor.

Inform your doctor if the following side effects seem severe:
Anxiety, nervousness, headache, sleeping trouble, stomach upset, nausea, sneezing, nasal stuffiness, muscle pain, decreased sexual function or desire, blurred vision, thirst, ringing in the ears, weakness and tiredness.
Notify your doctor immediately if you develop:
skin rash, confusion, mood changes, hallucinations, vomiting, severe diarrhea, breathing trouble.

Tell your doctor of all over-the-counter and prescription medication you may use, especially: cough medication, diarrhea medication, narcotic medication. Do not start or stop any medicine without doctor or pharmacist approval.

If overdose is suspected, contact your local poison control center or emergency room immediately.

It is recommended you carry medical identification stating you are taking this drug so that appropriate treatment can be given in a medical emergency.

If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.

This medication is used to maintain a drug-free state in those previously addicted to opiates. Naltrexone is also used in the treatment of alcoholism.

Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat and light. Do not store in the bathroom.

Naltrexone can cause liver problems when given in doses that are too large. Stop using this medication and notify your doctor immediately if symptoms of liver problems develop. This medication must not be used in patients who already have liver problems