Pyridostigmine affects chemicals in the body that are involved in the communication between nerve impulses and muscle movement.

Pyridostigmine is used to treat the symptoms of myasthenia gravis. It is also used in military personnel who have been exposed to nerve gas.

Pyridostigmine may also be used for purposes not listed in this medication guide.

You should not use pyridostigmine if you you have a bladder or bowel obstruction.

Pyridostigmine comes as a regular tablet, an extended-release (long-acting) tablet, and a syrup to take by mouth. It usually is taken once, twice, or several times a day, depending on the type of tablet. Your doctor may change your dose, depending on how you respond to the drug. When you first start taking pyridostigmine, your doctor may want you to keep a daily record of the time you take each dose, how long you feel better after taking each dose, and if you have side effects. This record will help the doctor decide how much drug is best for you. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take pyridostigmine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the extended-release tablets whole; do not chew or crush them.

Continue to take pyridostigmine even if you feel well. Do not stop taking pyridostigmine without talking to your doctor.

Pyridostigmine overdose can cause severe illness, including muscle weakness. It is very hard to tell the difference between too little and too much pyridostigmine. Call your doctor immediately if your symptoms become worse.

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take this medicine with food or milk if it upsets your stomach.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

The amount and timing of this medicine is extremely important to the success of your treatment. Carefully follow your doctor's instructions about how much medicine to take and when to take it.

Your doctor may occasionally change your dose to make sure you get the best results. You may be asked to keep a daily record of when you took each dose and how long the effects lasted. This will help your doctor determine if your dose needs to be adjusted.

If you need surgery, tell the surgeon ahead of time that you are using pyridostigmine. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture and heat.

Keep the tablets in their original container, along with the canister of moisture-absorbing preservative that comes with this medicine.

You should not use pyridostigmine if you are allergic to it, or if you have a bladder or bowel obstruction.

To make sure you can safely take pyridostigmine, tell your doctor if you have any of these other conditions:

• asthma; or

• kidney disease.

FDA pregnancy category C. It is not known whether pyridostigmine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using pyridostigmine.

It is not known whether pyridostigmine passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Pyridostigmine is not approved for use by anyone younger than 18 years old.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea, vomiting, diarrhea, stomach cramps, sweating, blurred vision, drooling, and weak or shallow breathing.

Worsening muscle weakness, or no change in your myasthenia gravis symptoms, may also be signs of overdose.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Pyridostigmine may cause an upset stomach. Take pyridostigmine with food or milk.

This medication may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Drinking alcohol can increase certain side effects of pyridostigmine.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using pyridostigmine and call your doctor at once if you have any of these serious side effects:

• extreme muscle weakness;

• loss of movement in any part of your body;

• weak or shallow breathing;

• slurred speech, vision problems; or

• worsening or no improvement in your symptoms of myasthenia gravis.

Common side effects of pyridostigmine may include:

• stomach pain, nausea, vomiting, diarrhea;

• muscle cramps, twitching;

• sweating, increased salivation;

• cough with mucus;

• rash; or

• blurred vision.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Other drugs may interact with pyridostigmine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to pyridostigmine.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.