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Some commonly used brand names are:

In the U.S.—

  • Orlaam

Other commonly used names are LAAM , LAM , levacetylmethadol , levo-alpha-acetylmethadol , levomethadyl acetate , and MK790 .

Not commercially available in Canada.


  • Opioid (narcotic) abuse therapy adjunct


Levomethadyl (lee-voe-METH-a-dil) belongs to the group of medicines known as narcotic analgesics (nar-KOT-ik an-al-GEE-zicks) . It is used as a substitute for illegal narcotics in addiction treatment programs. This medicine is not a cure for addiction. It is used as part of an overall program that may include counseling, attending support group meetings, and other treatment recommended by your doctor.

Levomethadyl helps prevent the withdrawal symptoms that may occur when an addict stops using other narcotics. In detoxification programs, the amount of levomethadyl used is slowly decreased until an addict becomes drug-free. In maintenance programs, it is used on a long-term basis to help narcotic addicts stay away from street drugs. With long-term use, levomethadyl may decrease an addict's craving for other narcotics.

Another narcotic, methadone, is also used in detoxification and maintenance programs. Methadone begins to work faster than levomethadyl does when treatment is started, but it has to be taken every day. Levomethadyl starts to work slowly, but it does not have to be taken every day. Therefore, some people may start treatment with methadone and then change over to levomethadyl after several weeks. Other people may receive only one medicine or the other during the entire time of treatment. Your doctor and your counselor at the clinic will decide on the best treatment plan for you.

In the U.S., levomethadyl is available only in government-approved treatment clinics, in the following dosage form:

  • Oral
  • Oral solution (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 will do. This is a decision you and your doctor will make. For levomethadyl, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to levomethadyl. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Methadone is the best medicine for treating pregnant narcotic addicts. Although there may be rare exceptions, levomethadyl is not recommended for use by pregnant women. Breathing problems and withdrawal symptoms are likely to occur in babies born to mothers who use levomethadyl during pregnancy. Also, although levomethadyl did not cause birth defects, it caused early deliveries and stillbirths in animal studies. In the U.S., the law requires that women who may become pregnant must be given pregnancy tests before levomethadyl treatment is started and once a month during treatment.

Breast-feeding—It is not known whether levomethadyl passes into the breast milk in amounts that may cause dependence or other side effects in nursing babies. Breast-feeding mothers who wish to use levomethadyl should discuss this with their doctor.

Children—In the U.S., the law does not allow levomethadyl to be used for treating addicts younger than 18 years of age.

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

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking levomethadyl, it is especially important that your health care professional know if you are taking any of the following:

  • Alcohol or
  • Barbiturates or
  • Carbamazepine (e.g., Tegretol) or
  • Chloramphenicol (e.g., Chloromycetin) or
  • Cimetidine (e.g., Tagamet) or
  • Corticosteroids (cortisone-like medicines) or
  • Diltiazem (e.g., Cardizem) or
  • Disulfiram (e.g., Antabuse) or
  • Divalproex (e.g., Depakote) or
  • Erythromycins (medicine for infection) or
  • Griseofulvin (e.g., Fulvicin) or
  • Isoniazid (e.g., INH, Nydrazid) or
  • Oral contraceptives (birth control pills) containing estrogen or
  • Phenylbutazone (e.g., Butazolidin) or
  • Phenytoin (e.g., Dilantin) or
  • Primidone (e.g., Mysoline) or
  • Quinine (e.g., Quinamm) or
  • Rifampin (e.g., Rifadin)
  • Ranitidine (e.g., Zantac) or
  • Valproic acid (e.g., Depakene) or
  • Verapamil (e.g., Calan)—These medicines may change the way levomethadyl works in your body. Some of them may cause levomethadyl to start working more quickly, but to keep working for a shorter time, than usual. Others may cause levomethadyl to start working more slowly, but to keep working for a longer time, than usual
  • Buprenorphine (e.g., Buprenex) or
  • Butorphanol or (e.g., Stadol) or
  • Dezocine (e.g., Dalgan) or
  • Nalbuphine (e.g., Nubain) or
  • Pentazocine (e.g., Talwin)—Like levomethadyl, these medicines are narcotics. However, they may cause withdrawal symptoms if they are taken during levomethadyl treatment
  • Central nervous system (CNS) depressants (medicine that causes drowsiness) or
  • Other narcotics or
  • Tricyclic antidepressants (medicine for depression)—The chance of serious side effects is increased; deaths have occurred when people continued to use CNS depressant ``street'' drugs, including other narcotics, while taking levomethadyl
  • Naltrexone (e.g., ReVia)—Naltrexone blocks the effects of levomethadyl and will cause withdrawal symptoms if taken during levomethadyl treatment

Other medical problems—The presence of other medical problems may affect the use of levomethadyl. Make sure you tell your doctor if you have any other medical problems, especially:

  • Asthma, emphysema, or other chronic lung disease, or
  • Brain disease or head injury or
  • Colitis or
  • Crohn's disease or
  • Enlarged prostate or problems with urination or
  • Gallbladder disease or gallstones or
  • Heart disease or
  • High blood pressure—Levomethadyl has side effects that could be dangerous to people with these conditions
  • Kidney disease or
  • Liver disease or
  • Underactive thyroid—The chance of side effects may be increased

Proper Use of This Medicine

Most patients are given their dose of levomethadyl at the clinic. You may be able to take some doses of your levomethadyl at home if your health care professional feels you are responsible to do that. Most people will have to go to the clinic 3 times a week.

Dosing—The dose of levomethadyl will be different for different patients. The following information includes only the average doses of levomethadyl.

  • For oral dosage form (oral solution):
    • For treating narcotic addiction:
      • Adults—The first dose of levomethadyl for patients who have not started treatment with methadone is between 20 and 40 milligrams (mg). The first dose for patients who have been receiving methadone will be a little higher than the amount of methadone that was being taken every day, but not more than 120 mg. Your doctor will then adjust your dose, depending on whether you experience withdrawal symptoms or side effects after the first dose. More than one change in the dose may be needed, until the right dose for you has been found.
        Most people will receive levomethadyl 3 times a week, either on Monday, Wednesday, and Friday or on Tuesday, Thursday, and Saturday. Some people need a larger dose on Friday or Saturday, so that the medicine will last until the next visit. In detoxification programs, the dose of levomethadyl will gradually be decreased until the patient is able to stop taking it. In maintenance programs, treatment may be continued as long as needed.
        If you miss one treatment in your program, your health care professional will have to adjust your treatment schedule and dose; you may need to start a new program with a lower starting dose if you miss more than one treatment or have been off the treatment for more than one week.
      • Children—In the U.S., levomethadyl cannot be used for patients younger than 18 years of age.

Precautions While Using This Medicine

Taking levomethadyl is only part of your treatment. Your doctor and your counselor at the clinic will make a treatment plan for you to follow. This plan may include seeing your counselor at the clinic regularly, attending support group meetings, and making changes in your lifestyle that will help you stay away from illegal drugs. The success of your treatment will depend on how carefully you follow your treatment plan .

This medicine will add to the effects of alcohol and other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or other narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. It is very important that you do not drink alcoholic beverages or take any CNS depressants during levomethadyl treatment unless you have been directed to do so by a doctor who knows that you are taking levomethadyl . Even if you continue to have some withdrawal symptoms and to crave narcotics for a while after levomethadyl treatment has been started, do not use illegal narcotics or other CNS depressant ``street'' drugs. Taking ``street'' drugs together with levomethadyl has caused some people to die from an overdose .

Levomethadyl may cause some people to become drowsy, especially when treatment is started or the dose is increased. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are drowsy or are not alert and clearheaded . This effect usually goes away after a few days, when your body gets used to the medicine. However, tell your counselor at your next visit to the clinic if any dose causes drowsiness that is severe enough to interfere with your activities .

Dizziness, lightheadedness, or even fainting may occur when you get up suddenly from a lying or sitting position. Getting up slowly may help lessen this problem . Also, lying down for a while may relieve dizziness or lightheadedness.

Tell all health care professionals you go to that you are taking levomethadyl . This is especially important if any kind of surgery or emergency treatment is needed. Serious side effects can occur if your health care professional gives you certain other medicines without knowing that you are taking levomethadyl.

Using narcotics such as levomethadyl for a long time can cause severe constipation. To prevent this, your counselor may direct you to take laxatives, drink a lot of fluids, or increase the amount of fiber in your diet. Be sure to follow the directions carefully, because continuing constipation can lead to more serious problems.

Levomethadyl may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if dry mouth continues for more than 2 weeks, check with your dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

For women only:

  • Although there may be rare exceptions, levomethadyl is not recommended for use by pregnant women . Pregnancy tests will be given once a month during treatment. If you miss any of these tests you may not be able to continue receiving levomethadyl .
  • Women who may become pregnant should use effective birth control during levomethadyl treatment . If you are not sure what method of birth control will work best for you, check with your counselor at the clinic.
  • If you plan to become pregnant, you should first discuss your plans with your doctor or your counselor. They can arrange for you to receive methadone instead of levomethadyl.
  • If you think you have become pregnant during treatment, tell your counselor right away .

Some people may be transferred to methadone after receiving levomethadyl for a while. If you are given any take-home doses of methadone, do not take the first dose of methadone for at least 48 hours (2 days) after your last dose of levomethadyl . Taking the 2 medicines too close together may cause an overdose.

If you think you may have taken an overdose of narcotics, get emergency help right away . Taking an overdose of narcotics, or taking alcohol or CNS depressants with narcotics, may lead to unconsciousness or death. Signs of overdose include convulsions (seizures); confusion; severe dizziness, drowsiness, nervousness, restlessness, or weakness; and very slow or troubled breathing. It is very important that the emergency room doctor knows that you are physically dependent on a narcotic called levomethadyl, that using naloxone to treat your overdose is very likely to cause withdrawal symptoms, and that you will need to be watched for a long time because levomethadyl's effects last for several days . However, you may not be able to give this information to the doctor yourself. Therefore, you should direct friends and family members to give this information to the doctor, if necessary .

Side Effects of This Medicine

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

Get emergency help immediately if any of the following side effects occur:

Signs and symptoms of overdose

Cold, clammy skin; confusion; convulsions (seizures); dizziness (severe); drowsiness (severe); low blood pressure; nervousness or restlessness (severe); pinpoint pupils of eyes; slow heartbeat; slow or troubled breathing; weakness (severe)

Also, tell your counselor at the clinic as soon as possible if any of the following side effects occur:

Less common

Mental depression; skin rash; swelling of face, fingers, feet, and/or lower legs; weight gain

At each visit to the clinic, be sure to tell your counselor if any of the following side effects occurred after your last dose of levomethadyl:

Signs of too much levomethadyl

Drowsiness (severe); feeling ``wired''

Signs of not enough levomethadyl (withdrawal symptoms)

Body aches, diarrhea; fast heartbeat; gooseflesh; increased sweating; loss of appetite; nausea or vomiting; nervousness, restlessness, or irritability; runny nose; shivering or trembling; sneezing; stomach cramps; trouble in sleeping; unexplained fever; unusually large pupils of eyes; weakness; yawning

The withdrawal side effects listed above may also occur after levomethadyl treatment has been stopped or during a changeover from levomethadyl to methadone. Always check with your counselor at the clinic if withdrawal side effects occur after you stop taking levomethadyl .

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your counselor at the clinic if any of the following side effects continue or are bothersome:

More common

Abdominal or stomach pain; constipation; general feeling of discomfort or illness; joint pain; sexual problems in males

Less common or rare

Anxiety; back pain; blurred vision; chills; coughing; decreased desire for sex; dizziness, lightheadedness, or feeling faint when rising from a lying or sitting position; drowsiness; dry mouth; false sense of well-being; flu-like symptoms; headache; hot flashes; muscle pain; unusual dreams; watery eyes

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Developed: 08/11/95
Revised: 08/06/2001

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