Usual Adult Dose for Myasthenia Gravis

Immediate-release tablets and syrup: 60 to 1500 mg daily (usually 600 mg/day divided into 5 or 6 doses) spaced to provide maximum relief

Sustained-release: 180 to 540 mg once or twice daily (separated by at least 6 hours); it may be necessary to use the immediate-release tablets or oral solution in conjunction with the sustained-release tablets for optimum control

Comments:

• Not all products are approved for the same indications. Refer to the manufacturer product information for indications.

Use: Myasthenia gravis

Usual Adult Dose for Reversal of Nondepolarizing Muscle Relaxants

The IV dose should be individualized. The dosage information presented here is derived from studies based upon units of drug per unit of body weight and is intended to serve as a guide only:

• When this drug is given IV to reverse the action of muscle relaxant drugs, it is recommended that atropine sulfate (0.6 to 1.2 mg) or an equipotent dose of glycopyrrolate be given immediately prior to or simultaneously with the administration of this drug to minimize excessive secretions and bradycardia.
• Reversal doses range from 0.1 to 0.25 mg/kg.
• The onset time to peak effect is dose-dependent; return of twitch height to 90% of control occurs within approximately 6 minutes following administration of a 0.25 mg/kg dose; at lower doses, full recovery usually occurs within 15 minutes in most patients, although others may require a half-hour or more.

Comments:

• Not all products are approved for the same indications. Refer to the manufacturer product information for indications.
• Satisfactory reversal can be evident by adequate voluntary respiration, respiratory measurements and use of a peripheral nerve stimulator device.
• It is recommended that the patient be well ventilated and a patent airway maintained until complete recovery of normal respiration.

Use: As a reversal agent or antagonist to the neuromuscular blocking effects of nondepolarizing muscle relaxants

Usual Adult Dose for Nerve Agent Pretreatment

Soman pretreatment:
30 mg orally every 8 hours starting at least several hours prior to exposure to soman; pretreatment has been used for up to 14 to 21 days

• Duration of use: The benefits and risks of use beyond 14 consecutive days have not been definitively established; therefore, continued use beyond 14 consecutive days should be evaluated in the context of the likelihood of exposure to soman nerve agent.

Comments:

• Not all products are approved for the same indications. Refer to the manufacturer product information for indications.
• At the first sign of nerve agent poisoning (runny nose, watery eyes, small, pinpoint pupils, eye pain, blurred vision, drooling, excessive sweating, cough, chest tightness, rapid breathing, diarrhea, increased urination, confusion, drowsiness, weakness, headache, nausea, vomiting, abdominal pain, slow or fast heart rate, abnormally low or high blood pressure) this drug should be discontinued and treatment with atropine and 2-PAM should be instituted immediately.
• This drug is not effective and should not be taken at the time of, or after exposure to, nerve agents. Immediate treatment with parenteral atropine and 2-PAM is required if nerve agent exposure occurs.

Use: For pretreatment against the lethal effects of soman nerve agent poisoning in conjunction with protective garments, including a mask. At the first sign of nerve agent poisoning, this drug should be stopped, and atropine and pralidoxime (2-PAM) therapy started immediately.

Renal Dose Adjustments

Lower doses may be required; however, no specific guidelines have been suggested. Caution recommended.

Liver Dose Adjustments

Data not available

Precautions

US BOXED WARNINGS:

• This drug should be administered by trained individuals familiar with its actions, characteristics, and hazards.

CAUTION: THIS DRUG IS USED AS A PRETREATMENT ONLY FOR SOMAN EXPOSURE; AFTER EXPOSURE TO SOMAN, USE ATROPINE AND 2-PAM (ALWAYS WEAR PROTECTIVE GARMENTS):

• This drug is for use as a pretreatment for exposure to soman nerve agent. It alone will not protect against exposure to soman. The efficacy is dependent upon the rapid use of atropine and pralidoxime (2-PAM) after soman exposure.
• Primary protection against exposure to chemical nerve agents is the wearing of protective garments including masks, hoods, and overgarments.
• Individuals must not rely solely upon pretreatment with this drug and on atropine and 2-PAM to provide complete protection from poisoning by soman nerve agent.
• DO NOT take this drug after exposure to soman.
• If this drug is taken immediately before exposure (e.g., when the gas attack alarm is given) or at the same time as poisoning by soman, it is not expected to be effective and may exacerbate the effects of a sublethal exposure to soman.

CONTRAINDICATIONS:

• Hypersensitivity to the active component or any of the ingredients
• Mechanical gastrointestinal or urinary obstruction (oral)
• Caution should be used in administration to patients with bronchial asthma (oral formulation)
• In patients with thrombocytopenia, coagulation disorder, or an increase in bleeding tendency due to other causes (IV)

This drug is not recommended for use in children.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

General:

• When this drug is used as a pretreatment for exposure to soman nerve agent, it alone will not protect against exposure to soman. The efficacy is dependent upon the rapid use of atropine and pralidoxime (2-PAM) after soman exposure.
• Primary protection against exposure to chemical nerve agents is the wearing of protective garments including masks, hoods, and overgarments.

Patient advice:

• Patients should be advised that the use of this drug may not restore muscle strength to normal and should be cautioned not to increase their dose above the maximum response level in an attempt to relieve all symptoms.

Frequently asked questions

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