In this Article

• What is methsuximide (Celontin)?
• What are the possible side effects of methsuximide (Celontin)?
• What is the most important information I should know about methsuximide (Celontin)?
• What should I discuss with my healthcare provider before taking methsuximide (Celontin)?
• How should I take methsuximide (Celontin)?
• What happens if I miss a dose (Celontin)?
• What happens if I overdose (Celontin)?
• What should I avoid while taking methsuximide (Celontin)?
• What other drugs will affect methsuximide (Celontin)?
• Where can I get more information?

What should I discuss with my healthcare provider before taking methsuximide (Celontin)?

You should not use this medication if you are allergic to methsuximide or to other seizure medications.

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

• lupus;
• liver disease;
• kidney disease; or
• a history of depression, mental illness, or suicidal thoughts or actions.

You may have thoughts about suicide while taking this medication. Tell your doctor if you have new or worsening depression or suicidal thoughts during the first several months of treatment, or whenever your dose is changed.

Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits. Do not miss any scheduled appointments.

It is not known whether methsuximide will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

Although methsuximide might harm an unborn baby, having a seizure during pregnancy could harm both mother and baby. If you become pregnant while taking methsuximide, do not stop taking it without your doctor's advice.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of methsuximide on the baby.

It is not known whether methsuximide passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take methsuximide (Celontin)?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Methsuximide can lower blood cells that help your body fight infections. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood may need to be tested often. Visit your doctor regularly.

Call your doctor at once if you have any unusual bleeding, weakness, or any signs of infection, including flu-like symptoms. These symptoms may first develop even after you have been using the medication for several months.

Do not stop using methsuximide without first talking to your doctor, even if you feel fine. You may have increased seizures if you stop using methsuximide suddenly. You may need to use less and less before you stop the medication completely.

Contact your doctor if your seizures get worse or you have them more often while taking methsuximide.

Wear a medical alert tag or carry an ID card stating that you take methsuximide. Any medical care provider who treats you should know that you take seizure medication.

Use methsuximide regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

Store at room temperature away from moisture, heat, and light. High heat can cause a methsuximide capsule to melt.