NALTREXONE (Systemic)

Some commonly used brand names are:

In the U.S.?

• ReVia
• Vivitrol

In Canada?

• ReVia

Generic name product may be available in the U.S.

Category

• Opioid (narcotic) abuse therapy adjunct
• Opioid (narcotic) antagonist
• Alcoholabuse therapy adjunct

Description

Naltrexone (nal-TREK-zone) is used to help narcotic addicts who have stopped takingnarcotics to stay drug-free. It is also used to help alcoholics stay alcohol-free.The medicine is not a cure for addiction. It is used as part of an overallprogram that may include counseling, attending support group meetings, andother treatment recommended by your doctor.

Naltrexone is not a narcotic. It works by blocking the effects of narcotics,especially the ?high? feeling that makes you want to use them.It also may block the ?high? feeling that may make you want touse alcohol. It will not produce any narcotic-like effects or cause mentalor physical dependence. It will not prevent you from becoming impaired whiledrinking alcohol.

Naltrexone will cause withdrawal symptoms in people who are physicallydependent on narcotics. Therefore, naltrexone treatment is started after youare no longer dependent on narcotics. The length of time this takes may dependon which narcotic you took, the amount you took, and how long you took it.Before you start taking this medicine, be sure to tell your doctor if youthink you are still having withdrawal symptoms.

Naltrexone is available only with your doctor's prescription, in the followingdosage form:

Oral
• Tablets (U.S. and Canada)

Parenteral
• Injection (U.S.)

Before Using This Medicine

In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For naltrexone, thefollowing should be considered:

Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to naltrexone. Also tell your health care professional ifyou are allergic to any other substances, such as foods, preservatives, ordyes.

Pregnancy?Naltrexone has not been studied in pregnant women.However, studies in animals have shown that naltrexone causes unwanted effectswhen given in very large doses. Before taking this medicine, make sure yourdoctor knows if you are pregnant or if you may become pregnant.

Breast-feeding?It is not known whether naltrexone passes intothe breast milk. However, this medicine has not been reported to cause problemsin nursing babies.

Children?Naltrexone has been tested only in adult patientsand there is no specific information about its use in patients up to 18 yearsof age.

Older adults?Many medicines have not been studied specificallyin older people. Therefore, it may not be known whether they work exactlythe same way they do in younger adults or if they cause different side effectsor problems in older people. There is no specific information comparing the use of naltrexone in the elderly with use in other age groups.

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are takingnaltrexone, it is especially important that your health care professionalknow if you are taking any of the following:

• Opioid (Narcotic) analgesics (e.g., butorphanol [e.g., Stadol], codeine,hydrocodone [e.g., Hycodan], hydromorphone [e.g., Dilaudid], levorphanol [e.g.,Levo-Dromoran], meperidine [e.g., Demerol], methadone [e.g., Dolophine], morphine[e.g., MSIR], nalbuphine [e.g., Nubain], oxycodone [e.g., Roxicodone], propoxyphene[e.g., Darvon]) or
• Opioid-containing medications, other?The effects of these medicationsmay be blocked by naltrexone. Alternative medications for relief of pain shouldbe used in patients receiving naltrexone. Naltrexone may cause withdrawalin patients dependent on narcotics.

Other medical problems?The presence of other medicalproblems may affect the use of naltrexone. Make sure you tell your doctorif you have any other medical problems, especially:

• Hepatitis or other liver disease?The chance of side effectsmay be increased.

Proper Use of This Medicine

Take naltrexone regularly as ordered by your doctor. It may be helpfulto have someone else, such as a family member, doctor, or nurse, give youeach dose as scheduled.

Naltrexone injection can only be administered by a healthcare professional.

You will not be permitted to receive naltrexone injection if you have beenactively drinking.

Dosing?The dose of naltrexone will be different fordifferent patients. Follow your doctor's orders or thedirections on the label. The following information includes only theaverage doses of naltrexone. If your dose is different,do not change it unless your doctor tells you to do so.

• For oral dosage form (tablets):
  • For treating narcotic addiction:
    • Adults?25 milligrams (mg) (one-half tablet) for the first dose,then another 25 mg one hour later. After that, the dose is 350 mg a week.Your doctor will direct you to divide up this weekly dose and take naltrexoneaccording to one of the following schedules:
      • 50 mg (one tablet) every day; or
      • 50 mg a day during the week and 100 mg (two tablets) on Saturday;or
      • 100 mg every other day; or
      • 100 mg on Mondays and Wednesdays, and 150 mg (three tablets) on Fridays;or
      • 150 mg every three days.
    • Children and teenagers up to 18 years of age?Use and dose mustbe determined by your doctor.
  • For treating alcoholism:
    • Adults?The first dose may be 25 milligrams (mg) (one-half tablet).After that, the dose is 50 mg (one tablet) every day.
    • Children and teenagers up to 18 years of age?Use and dose mustbe determined by your doctor.
• For injectable dosage form
  • For treating alcoholism:
    • Adults?380 mg once a month injected into the muscle by yourdoctor.
    • Children and teenagers up to 18 years of age?Use and dose mustbe determined by your doctor.

Missed dose?If you miss a dose of the tablet form of this medicine,and your regular dosing schedule is:

• One tablet every day:
  • Take the missed dose as soon as possible. However, if you do notremember until the next day, skip the missed dose and go back to your regulardosing schedule. Do not double the next day's dose.
• One tablet every weekday and two tablets on Saturday:
  • If you miss a weekday dose, follow the directions for one tabletevery day.
  • If you miss the Saturday dose, take it as soon as possible. However,if you do not remember until Sunday, take one tablet on Sunday. Then go backto your regular dosing schedule on Monday.
• Two tablets every other day:
  • Take two tablets as soon as you remember, then skip a day, then goback to taking the medicine every other day; or
  • Take two tablets as soon as possible if you remember the same day.However, if you do not remember until the next day, take one tablet the nextday. Then go back to your regular dosing schedule.
• Two tablets on Monday and Wednesday and three tablets on Friday:
  • If you miss one of the Monday or Wednesday doses, take it as soonas possible. However, if you do not remember until the next day, take onetablet the next day. Then go back to your regular dosing schedule.
  • If you miss the Friday dose, take it as soon as possible if you rememberthe same day. However, if you do not remember until Saturday, take two tabletson Saturday. If you do not remember until Sunday, take one tablet on Sunday.Then go back to your regular dosing schedule on Monday.
• Three tablets every three days:
  • Take three tablets as soon you remember, then skip two days, thengo back to taking the medicine every three days; or
  • Take three tablets as soon as possible if you remember the same day.However, if you do not remember until the next day, take two tablets, thenskip a day and go back to your regular dosing schedule. If you do not rememberuntil the second day, take one tablet. Then go back to your regular dosingschedule.

If you miss a dose of the injection form of this medicine, you should receivethe next dose as soon as possible.

Storage?To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store this medicine in the bathroom, near the kitchen sink,or in other damp places. Heat or moisture may cause the medicine to breakdown.
• Do not keep outdated medicine.

Precautions While Using This Medicine

It is very important that your doctor check your progress atregular visits. Your doctor may want to do certain blood tests to seeif the medicine is causing unwanted effects.

Remember that use of naltrexone is only part of your treatment. Be sure that you follow all of your doctor's orders, includingseeing your therapist and/or attending support group meetings on a regularbasis.

Do not try to overcome the effects of naltrexone bytaking narcotics. To do so may cause coma or death. You may be moresensitive to the effects of narcotics than you were before beginning naltrexonetherapy.

Naltrexone also blocks the useful effects of narcotics. Always use a non-narcotic medicine to treat pain, diarrhea, or cough.If you have any questions about the proper medicine to use, check with yourhealth care professional.

Naltrexone will not prevent you from becoming impaired when you drink alcohol. Do not take naltrexone in order to drive or perform otheractivities while under the influence of alcohol.

After naltrexone is injected into your body, it is impossible to removeit.

Never share this medicine with anyone else, especiallysomeone who is using narcotics. Naltrexone causes withdrawal symptomsin people who are using narcotics.

Tell all medical doctors, dentists, and pharmacistsyou go to that you are taking naltrexone.

It is recommended that you carry identification statingthat you are taking naltrexone. Identification cards may be availablefrom your doctor.

You may experience a reaction at the site of the naltrexone injection includingpain, tenderness, thickening of the skin, and itching. If this skin reactionbecomes worse or does not improve in one month after receiving the injection, you should contact your doctor immediately.

You may experience nausea after the first injection of this medicine thatshould be mild and subside a few days afterwards. You will be less likelyto have nausea with your next injections.

Side Effects of This Medicine

Along with its needed effects,a medicine may cause some unwanted effects. Although not all of these sideeffects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possibleif any of the following side effects occur:

Less common

Skin rash

Rare

Abdominal or stomach pain (severe); blurred vision or aching, burning, or swollen eyes; chest pain; confusion; discomfort while urinating and/or frequent urination; fever; hallucinations (seeing, hearing, or feelingthings that are not there); itching; mental depression or other mood or mental changes; ringing or buzzing in ears; shortnessof breath; swelling of face, feet, or lower legs; weight gain

Other side effects may occur that usually donot need medical attention. These side effects may go away during treatmentas your body adjusts to the medicine. However, check with your doctor if anyof the following side effects continue or are bothersome:

More common

Abdominal or stomach cramping or pain (mild or moderate); anxiety, nervousness, restlessness, and/or trouble in sleeping; headache; joint or musclepain; nausea or vomiting; unusual tiredness

Less common or rare

Bleeding, blistering, burning, coldness, discolorationof skin, feeling of pressure, hives, infection, inflammation, itching, lumps,numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness,tingling, ulceration, or warmth at site of injection; chills; constipation; cough,hoarseness, runny or stuffy nose, sinus problems, sneezing, and/or sore throat; diarrhea; dizziness; fast or pounding heartbeat; increasedthirst; irritability; lossof appetite; sexual problems in males

Other side effects not listed above,possibly including withdrawal symptoms, may also occur in some patients. Ifyou notice any other effects, check with your doctor.