Seromycin

Seromycin is part of the drug class:

• Antibiotics for Treatment of Tuberculosis

Take all of the cycloserine that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated.

Avoid alcohol while taking cycloserine. Alcohol will increase your risk of having a seizure during cycloserine treatment. Alcohol will also increase dizziness and drowsiness.

Use caution when driving, operating machinery, or performing other hazardous activities. Cycloserine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Call your doctor immediately if you experience a skin rash, mental confusion, dizziness, headache, or tremors (shaking).

You cannot take cycloserine if you

• have epilepsy,

• suffer from depression,

• have an anxiety disorder,

• have a psychotic or psychiatric disorder,

• have kidney disease, or

• drink alcohol on a daily basis.

Cycloserine is in the FDA pregnancy category C. This means that it is not known whether cycloserine will harm an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant

Cycloserine passes into breast milk, and it is not known whether cycloserine will harm a nursing baby. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.

If you experience any of the following serious side effects, seek emergency medical attention or contact your doctor immediately:

• an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);

• seizures;

• numbness or tingling in your hands or feet;

• a skin rash;

• confusion or abnormal behavior;

• tremors (shaking);

• headache;

• drowsiness;

• dizziness;

• difficulty speaking; or

• irritability.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome. You may report side effects to FDA at 1-800-FDA-1088.

• Advise patients that poor compliance with antituberculosis regimens can result in treatment failure and development of drug-resistant TB, which can be life-threatening and lead to other serious health risks.100

• Importance of avoiding excessive concurrent use of alcohol.102

• Importance of notifying clinicians if allergic dermatitis or symptoms of CNS toxicity (seizures, psychosis, somnolence, depression, confusion, hyperreflexia, headache, tremor, vertigo, paresis, dysarthria) occur.102

• Importance of informing clinician of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.102

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.102

• Importance of informing patients of other important precautionary information.102 (See Cautions.)

Cycloserine may be taken after meals if it upsets your stomach.

To help clear up your infection completely, it is very important that you keep taking this medicine for the full time of treatment , even if you begin to feel better after a few weeks. If you are taking this medicine for TB, you may have to take it every day for as long as 1 to 2 years or more. If you stop taking this medicine too soon, your symptoms may return.

This medicine works best when there is a constant amount in the blood or urine. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times day and night. For example, if you are to take 2 doses a day, the doses should be spaced about 12 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your health care professional.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For the oral dosage form (capsules):
  • For treatment of tuberculosis:
    • Adults and teenagers—250 milligrams (mg) two times a day to start. Your doctor may slowly increase your dose up to 250 mg three or four times a day. This medicine must be taken along with other medicines to treat tuberculosis.
    • Children—Use and dose must be determined by your doctor. Doses of 10 to 20 mg per kilogram (4.5 to 9.1 mg per pound) of body weight per day have been used. This medicine must be taken along with other medicines to treat tuberculosis.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Administration of Seromycin should be discontinued or the dosage reduced if the patient develops allergic dermatitis or symptoms of CNS toxicity, such as convulsions, psychosis, somnolence, depression, confusion, hyperreflexia, headache, tremor, vertigo, paresis, or dysarthria.

The toxicity of Seromycin is closely related to excessive blood levels (above 30 μg/mL), as determined by high dosage or inadequate renal clearance. The ratio of toxic dose to effective dose in tuberculosis is small.

The risk of convulsions is increased in chronic alcoholics.

Patients should be monitored by hematologic, renal excretion, blood level, and liver function studies.

Pregnancy Category C

A study in 2 generations of rats given doses up to 100 mg/kg/day demonstrated no teratogenic effect in offspring. It is not known whether cycloserine can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Seromycin should be given to a pregnant woman only if clearly needed.

Safety and effectiveness in pediatric patients have not been established.

Acute toxicity from cycloserine can occur if more than 1 g is ingested by an adult. Chronic toxicity from cycloserine is dose related and can occur if more than 500 mg is administered daily. Patients with renal impairment will accumulate cycloserine and may develop toxicity if the dosing regimen is not modified. Patients with severe renal impairment should not receive the drug. The central nervous system is the most common organ system involved with toxicity. Toxic effects may include headache, vertigo, confusion, drowsiness, hyperirritability, paresthesias, dysarthria, and psychosis. Following larger ingestions, paresis, convulsions, and coma often occur. Ethyl alcohol may increase the risk of seizures in patients receiving cycloserine.

The oral median lethal dose in mice is 5290 mg/kg.

To obtain up–to–date information about the treatment of overdose, a good resource is your certified Regional Poison Control Center. Telephone numbers of certified poison control centers are listed in the Physicians’ Desk Reference (PDR). In managing overdosage, consider the possibility of multiple drug overdoses, interaction among drugs, and unusual drug kinetics in your patient.

Overdoses of cycloserine have been reported rarely. The following is provided to serve as a guide should such an overdose be encountered.

Protect the patient’s airway and support ventilation and perfusion. Meticulously monitor and maintain, within acceptable limits, the patient’s vital signs, blood gases, serum electrolytes, etc. Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage; consider charcoal instead of or in addition to gastric emptying. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient’s airway when employing gastric emptying or charcoal.

In adults, many of the neurotoxic effects of cycloserine can be both treated and prevented with the administration of 200 to 300 mg of pyridoxine daily.

The use of hemodialysis has been shown to remove cycloserine from the bloodstream. This procedure should be reserved for patients with life-threatening toxicity that is unresponsive to less invasive therapy.