Ruzurgi (Oral)

Amifampridine is used to treat Lambert-Eaton myasthenic syndrome (LEMS), which is a rare autoimmune disease. In LEMS, the immune system attacks the connection between the nerve and muscle (neuromuscular junction), preventing nerve cells from sending signals to muscle cells. This results in muscle weakness in the arms or legs.

This medicine is available only with your doctor's prescription.

It is very important that your doctor checks you or your child's progress at regular visits to ensure this medicine is working properly.

This medicine may increase your risk for seizures and should not be given to patients who have had seizures.

This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and require immediate medical attention. Tell your doctor right away if you have a rash, itching, hoarseness, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth after using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, you and your doctor will consider the risks of taking the medicine against the benefits it may provide. Here are some important points to consider:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know about any other allergies you may have, such as to foods, dyes, preservatives, or animals. For over-the-counter products, carefully read the label or package ingredients.

Pediatric

There have not been appropriate studies on how amifampridine affects children younger than 6 years old. Its safety and effectiveness in this age group have not been established.

Geriatric

There is no information available on how Ruzurgi® affects older adults. Studies done so far have not shown any specific problems in older patients that would limit the usefulness of Firdapse® in this age group. However, older adults are more likely to have age-related liver, kidney, or heart issues, which may require caution and dose adjustments for those taking this medicine.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits and risks before taking this medication during breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while others can be used together even if there might be interactions. In such cases, your doctor may need to adjust the dose or take other precautions. It is important for your healthcare professional to know if you are taking any of the medicines listed below while using this medicine. The following interactions are significant but may not include all possible interactions.

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in certain situations. If both medicines are prescribed together, your doctor may adjust the dose or frequency for one or both of the medicines.

• Acetophenazine
• Aclidinium
• Acrivastine
• Alcaftadine
• Alfentanil
• Amantadine
• Ambenonium
• Amdinocillin
• Amdinocillin Pivoxil
• Amineptine
• Aminophylline
• Amitriptylinoxide
• Amoxapine
• Amphetamine
• Ampicillin
• Anisotropine
• Antazoline
• Atropine
• Azatadine
• Azelastine
• Azlocillin
• Bacampicillin
• Baclofen
• Belladonna Alkaloids
• Benperidol
• Benzhydrocodone
• Benzphetamine
• Bepotastine
• Bornaprine
• Bromodiphenhydramine
• Bromperidol
• Brompheniramine
• Buclizine
• Bupivacaine
• Butorphanol
• Butriptyline
• Butylscopolamine
• Carbenicillin
• Carbinoxamine
• Chlorambucil
• Chlorotrianisene
• Chlorpheniramine
• Chlorphenoxamine
• Cimetropium
• Cinnarizine
• Clemastine
• Clemizole
• Clidinium
• Cloxacillin
• Cocaine
• Codeine
• Conjugated Estrogens
• Cyclacillin
• Cyclizine
• Cyclopentolate
• Cyclosporine
• Cyproheptadine
• Darifenacin
• Demecarium
• Dexbrompheniramine
• Dexchlorpheniramine
• Dextroamphetamine
• Dibenzepin
• Dicloxacillin
• Dicyclomine
• Dienestrol
• Diethylstilbestrol
• Difenoxin
• Dihydrocodeine
• Dimenhydrinate
• Dimethindene
• Diphenhydramine
• Diphenylpyraline
• Distigmine
• Dixyrazine
• Donepezil
• Dothiepin
• Doxylamine
• Echothiophate
• Edrophonium
• Emedastine
• Enflurane
• Epinastine
• Esterified Estrogens
• Estradiol
• Estramustine
• Estriol
• Estrone
• Estropipate
• Ethinyl Estradiol
• Ethopropazine
• Fentanyl
• Fesoterodine
• Flavoxate
• Floxacillin
• Flunarizine
• Glycopyrrolate
• Guanidine
• Hetacillin
• Homatropine
• Hydrocodone
• Hydromorphone
• Hydroxyamphetamine
• Hyoscyamine
• Indalpine
• Iprindole
• Isoflurophate
• Isoniazid
• Isopropamide
• Ketamine
• Ketotifen
• Levocabastine
• Levomilnacipran
• Levorphanol
• Lidocaine
• Lindane
• Lisdexamfetamine
• Lithium
• Lofepramine
• Loxapine
• Mebeverine
• Mebhydrolin
• Meclizine
• Mefenamic Acid
• Melitracen
• Melperone
• Mepenzolate
• Meperidine
• Mestranol
• Methamphetamine
• Methantheline
• Methdilazine
• Methicillin
• Methixene
• Methotrimeprazine
• Methylphenidate
• Metopimazine
• Mezlocillin
• Milnacipran
• Morphine
• Nalbuphine
• Nalidixic Acid
• Neostigmine
• Niaprazine
• Nortriptyline
• Olopatadine
• Opipramol
• Orphenadrine
• Oxacillin
• Oxatomide
• Oxycodone
• Oxymorphone
• Penicillin G
• Penicillin V
• Pentazocine
• Perazine
• Periciazine
• Phenindamine
• Pheniramine
• Phenylpropanolamine
• Phenyltoloxamine
• Physostigmine
• Pinaverium
• Piperacillin
• Pipotiazine
• Pirenzepine
• Pivampicillin
• Pizotyline
• Polyestradiol Phosphate
• Procaine
• Promazine
• Promestriene
• Propantheline
• Propicillin
• Propiverine
• Propizepine
• Propoxyphene
• Pyrilamine
• Quinestrol
• Remifentanil
• Rivastigmine
• Scopolamine
• Sibutramine
• Sufentanil
• Sulbenicillin
• Sultamicillin
• Tacrine
• Tapentadol
• Temocillin
• Theophylline
• Thiethylperazine
• Thiopropazate
• Thioproperazine
• Thonzylamine
• Tianeptine
• Tibolone
• Ticarcillin
• Timiperone
• Tiotropium
• Tramadol
• Trifluoperazine
• Triflupromazine
• Trimeprazine
• Tripelennamine
• Triprolidine
• Tropicamide
• Trospium
• Umeclidinium
• Valethamate

Interactions with Food/Tobacco/Alcohol

Some medicines should not be taken around the same time as certain foods, as interactions may happen. Drinking alcohol or using tobacco with certain medicines can also lead to interactions. Talk to your healthcare professional about using this medicine with food, alcohol, or tobacco.

Other Medical Problems

Other medical conditions may affect how you can use this medicine. Be sure to inform your doctor if you have any other medical issues, especially:

• Kidney disease or
• Liver disease—Use with caution. The effects may be stronger because the medicine may be removed from the body more slowly.

• Seizures, history of—This medicine should not be used in patients with this condition.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

• Arm or leg pain
• bladder pain
• bloating or swelling of the face, arms, hands, lower legs, or feet
• bloody or cloudy urine
• blurred vision
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• chest pain or tightness
• chills
• cough
• cough producing mucus
• diarrhea
• difficult, burning, or painful urination
• difficulty breathing or swallowing
• dizziness
• fever
• frequent urge to urinate
• general feeling of discomfort or illness
• headache
• hoarseness
• joint pain
• loss of appetite
• lower back or side pain
• muscle pains, spasms, or weakness
• nausea
• nervousness
• pounding in the ears
• rapid weight gain
• runny nose
• shivering
• slow or fast heartbeat
• sneezing
• sore throat
• sweating
• swollen, painful, or tender lymph glands in the neck, armpit, or groin
• trouble sleeping
• unusual tiredness or weakness
• unusual weight gain or loss
• vomiting

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Back pain
• blindness
• constipation
• decreased vision
• discouragement
• falls
• feeling cold
• feeling sad or empty
• heartburn
• irritability
• lack or loss of strength
• loss of interest or pleasure
• pale skin
• stomach pain
• trouble concentrating
• trouble breathing
• unusual bleeding or bruising

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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

In the U.S.

• Firdapse
• Ruzurgi

Available Dosage Forms:

• Tablet

Therapeutic Class: Central Nervous System Agent

Pharmacologic Class: Potassium Channel Blocker

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

This medicine comes with a Medication Guide and patient information leaflet. Read and follow these instructions carefully. Ask your doctor if you have any questions.

You may take this medicine with or without food.

The tablets may be divided in half at the score (line at the center) if you need less than a full tablet to get the right dose.

If you or your child are unable to swallow the tablets whole, you may prepare a suspension:

• Ruzurgi®: Mix 3 tablets with 30 milliliters (mL) of water in a 30-mL container, then shake the mixture well for 30 seconds. You may give the dose using an oral dosing syringe or feeding tube. Shake well before giving each dose.
• Firdapse®: Mix the tablet with 10 mL of sterile water for each tablet in a 50 to 100 mL container, wait for 5 minutes. Shake well for 30 seconds. You may give the dose using an oral dosing syringe or feeding tube. Shake well before giving each dose.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (tablets):For Lambert-Eaton myasthenic syndrome: Fidarpse®: Adults and children 6 years of age and older weighing 45 kilograms (kg) or more—Dose is based on body weight and must be determined by your doctor. At first, 15 milligrams (mg) to 30 mg given in 3 to 4 divided doses per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 80 mg per day. Children 6 years of age and older weighing less than 45 kg—Dose is based on body weight and must be determined by your doctor. At first, 5 mg to 15 mg given in 3 to 4 divided doses per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 40 mg per day. Children younger than 6 years of age—Use and dose must be determined by your doctor. Ruzurgi®: Children 6 to 16 years of age weighing 45 kilograms (kg) or more—Dose is based on body weight and must be determined by your doctor. At first, 15 milligrams (mg) to 30 mg given 2 to 3 divided doses per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 100 mg per day. Children 6 to 16 years of age weighing less than 45 kg—Dose is based on body weight and must be determined by your doctor. At first, 7.5 mg to 15 mg given 2 to 3 divided doses per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 50 mg per day. Children younger than 6 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Store Ruzurgi® tablets at room temperature for up to 3 months.

You may store the mixture in the refrigerator for up to 24 hours. Throw away any unused liquid after 24 hours.

• What is the difference between Ruzurgi and Firdapse?
• What is Firdapse (amifampridine) used to treat?