PYRIDOSTIGMINE

Brand & Generic Names

Mestinon
Mestinon Timespans
Regonol

Basic Information

• Habit forming? No
• Prescription needed? Yes
• Available as generic? No
• Drug class: Cholinergic, antimyasthenics

Uses

• Diagnosis and treatment of myasthenia gravis.
• Treatment of urinary retention and abdominal distention.
• Antidote to adverse effects of muscle relaxants used in surgery.

Dosage & Usage Information

How to take:
Tablet or syrup--Swallow with liquid or food to lessen stomach irritation.
Extended-release tablets--Swallow each dose whole. If you take regular tablets, you may chew or crush them.

When to take:
As directed, usually 3 or 4 times a day.

If you forget a dose:
Take as soon as you remember up to 2 hours late. If more than 2 hours, wait for next scheduled dose (don't double this dose).

What drug does:
Inhibits the chemical activity of an enzyme (cholinesterase) so nerve impulses can cross the junction of nerves and muscles.

Time lapse before drug works:
3 hours.

Don't take with:
Any other medicine without consulting your doctor or pharmacist.

Overdose

SYMPTOMS:
Muscle weakness or paralysis, cramps, twitching or clumsiness; severe diarrhea, nausea, vomiting, stomach cramps or pain; breathing difficulty; confusion, irritability, nervousness, restlessness, fear; unusually slow heartbeat; seizures; blurred vision; extreme fatigue.

WHAT TO DO:

• Dial 911 (emergency) or O (operator) for an ambulance or medical help. Then give first aid immediately.
• See EMERGENCY Information.

Possible Adverse Reactions or Side Effects

Life-threatening:

In case of overdose, see Overdose section.

Common:

• Mild diarrhea, nausea, vomiting, stomach cramps or pain.
• Excess saliva, unusual sweating.

Infrequent:

• Confusion, irritability.
• Constricted pupils, watery eyes, lung congestion, frequent urge to urinate.

Rare:

Bronchospasm, slow heartbeat, weakness.

Warnings & Precautions

Don't take if:

• You are allergic to any cholinergic* or bromide.
• You take mecamylamine.

Before you start, consult your doctor:

• If you plan to become pregnant within medication period.
• If you have bronchial asthma.
• If you have heartbeat irregularities.
• If you have urinary obstruction or urinary-tract infection.

Over age 60:
Adverse reactions and side effects may be more frequent and severe than in younger persons.

Pregnancy:
Safety not established. Decide with your doctor whether drug benefits justify risk to unborn child.

Breast-feeding:
No problems expected, but consult doctor.

Infants & children:
Not recommended.

Prolonged use:
Medication may lose effectiveness. Discontinuing for a few days may restore effect.

Skin & sunlight:
No problems expected.

Driving, piloting or hazardous work:
Don't drive or pilot aircraft until you learn how medicine affects you. Don't work around dangerous machinery. Don't climb ladders or work in high places. Danger increases if you drink alcohol or take medicine affecting alertness and reflexes, such as antihistamines, tranquilizers, sedatives, pain medicine, narcotics and mind-altering drugs.

Discontinuing:
Don't discontinue without doctor's advice until you complete prescribed dose, even though symptoms diminish or disappear.

Others:
No problems expected.

Possible Interaction with Other Drugs

GENERIC NAME	COMBINED EFFECT
------------------------	-----------------------
Anesthetics*,	Decreased pyridostigmine effect.
Antiarrhythmics*	Decreased pyridostigmine effect.
Anticholinergics*	Decreased pyridostigmine effect.
	May mask severe side effects.
Cholinergics*,	Reduced intestinal tract function.
other	Possible brain and nervous system
	toxicity.
Guanadrel	Decreased pyridostigmine effect.
Guanethidine	Decreased pyridostigmine effect.
Mecamylamine	Decreased pyridostigmine effect.
Nitrates*	Decreased pyridostigmine effect.
Procainamide	Decreased pyridostigmine effect.
Quinidine	Decreased pyridostigmine effect.

Possible Interaction with Other Substances

INTERACTS WITH	COMBINED EFFECT
---------------	---------------
Alcohol:	No proven problems with small
	doses.
Beverages:	None expected.
Cocaine:	Decreased pyridostigmine effect.
	Avoid.
Foods:	None expected.
Marijuana:	No proven problems.
Tobacco:	No proven problems.