Ruzurgi

Ruzurgi is a prescription medication used to treat Lambert-Eaton myasthenic syndrome (LEMS) in children aged 6 years of age to 16. LEMS is a disease in which the immune system attacks the body's own tissues interfering with the ability of nerve cells to send signals to muscle cells via acetylcholine release. Acetylcholine is a chemical messenger that triggers muscle contraction. In people with LEMS, levels of acetylcholine are not sufficient to allow normal muscle contractions, causing muscle weakness.

Ruzurgi belongs to a group of drugs called potassium channel blockers. The exact way Ruzurgi works is unknown, but it is thought to work by increasing the release of acetylcholine.

This medication comes in tablet form and is taken by mouth, with or without food.

Common side effects include tingling around the mouth, tongue, face, fingers, toes, and other body parts, stomach pain, and indigestion.

Ruzurgi is a prescription medicine used to treat Lambert-Eaton myasthenic syndrome (LEMS) in children 6 to less than 17 years of age.

This medication may be prescribed for other uses. Ask your doctor or pharmacist.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

• your body weight
• how you respond to this medication

The recommended dose in patients 6 to less than 17 years of age, weighing 45 kg or more: 15 mg to 30 mg daily, in divided doses (2 to 3 times per day). Increase daily in 5 mg to 10 mg increments, divided in up to 5 doses per day. The maximum total daily maintenance dosage is 100 mg.

The recommended dose in patients 6 to less than 17 years of age, weighing less than 45 kg:  7.5 mg to 15 mg daily, in divided doses (2 to 3 times per day). The maximum total daily maintenance dosage is 50 mg.

Ruzurgi may cause serious side effects including:

• Seizures. You could have a seizure even if you never had a seizure before. Do not take Ruzurgi if you have ever had a seizure. Stop taking Ruzurgi and call your doctor right away if you have a seizure while taking Ruzurgi.
• Serious allergic reactions, such as anaphylaxis. Ruzurgi can cause serious allergic reactions. Stop taking Ruzurgi and call your doctor right away or get emergency medical help if you have:
  • shortness of breath or trouble breathing 
  • swelling of your throat or tongue
  • hives

Do not take Ruzurgi if you:

• have ever had a seizure.
• are allergic to amifampridine or another aminopyridine. Talk to your doctor if you are not sure.

Serious side effects may occur. See "Ruzurgi Precautions" section.

The most common side effects of Ruzurgi include:

• tingling around the mouth, tongue, face, fingers, toes, and other body parts
• stomach pain
• indigestion
• dizziness
• nausea

Tell your doctor if you have any side effect that bothers you or does not go away.

These are not all the possible side effects of Ruzurgi.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Especially tell your healthcare provider if you take any of the following medicines:

• other medicines known to increase the risk of seizures such as aminopyridine medicines, including: 

  • compounded 3,4-diaminopyridine (amifampridine) 
  • amifampridine phosphate
  • 4-aminopyridine

• drugs with cholinergic effects (e.g., direct or indirect cholinesterase inhibitors), including: 

  • pyridostigmine
  • neostigmine
  • rivastigmine, donepezil, galantamine
  • pilocarpine
  • bethanechol
  • cevimeline

This is not a complete list of Ruzurgi drug interactions. Ask your doctor or pharmacist for more information.

Tell your doctor if you are pregnant or plan to become pregnant.

Animal studies to assess the potential adverse effects of this medication on embryofetal development have not been conducted. 

It is not known if Ruzurgi can harm yourvunborn baby. You and your doctor should decide if you will take Ruzurgi while you are pregnant.

Tell your healthcare provider if you are breastfeeding or plan to breastfeed.

It is not known if Ruzurgi passes into your breastmilk. Talk to your doctor about the best way to feed your baby while taking Ruzurgi.