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