Primidone, used alone or concomitantly with other anticonvulsants, is indicated in the control of grand mal, psychomotor, and focal epileptic seizures. It may control grand mal seizures refractory to other anticonvulsant therapy.
Primidone is contraindicated in: 1) patients with porphyria and 2) patients who are hypersensitive to phenobarbital (see ACTIONS ).
Primidone is contraindicated in: 1) patients with porphyria and 2) patients who are hypersensitive to phenobarbital (see ACTIONS ).
The abrupt withdrawal of antiepileptic medication may precipitate status epilepticus. The therapeutic efficacy of a dosage regimen takes several weeks before it can be assessed.
Primidone Tablets, USP 50 mg - NDC 72603-609-01 - 100s Bottle Label Primidone Tablets, USP 50 mg - NDC 72603-609-02 - 500s Bottle Label Primidone Tablets, USP 250 mg - NDC 72603-610-01 - 100s Bottle Label
| Class | Version | Type | Effective |
|---|---|---|---|
| PRIMIDONE Pharmacologic Class Indexing | 3 | Indexing - Pharmacologic Class | 20180813 |
| Product concept | Relation | Version | Effective |
|---|---|---|---|
| 3a6e0ba9-1dda-c47a-a8e3-5844e445a4f8 | Product name | 3 | 20250114 |
| 594e2c86-3079-4e6e-96c9-48f7a8afc78d | Product name | 1 | 20230718 |
| Package NDC | Product | Description | Form | Quantity | Strength | SPL version |
|---|---|---|---|---|---|---|
| 72603-609-01 | Primidone | 100 in 1 BOTTLE | TABLET | 100 | 1 | |
| 72603-609-02 | Primidone | 500 in 1 BOTTLE | TABLET | 500 | 1 | |
| 72603-610-01 | Primidone | 100 in 1 BOTTLE | TABLET | 100 | 1 |
| NDC | Dashboard title | SPL version | Validation | Dashboard ZIP |
|---|---|---|---|---|
| 72603-609 | PRIMIDONE TABLET [NORTHSTAR RX LLC] | 1 | Current NDC, 2 package rows | 20250523_182a424b-d142-48c9-996b-059c0885f528.zip |
| 72603-610 | PRIMIDONE TABLET [NORTHSTAR RX LLC] | 1 | Current NDC, 1 package rows | 20250523_182a424b-d142-48c9-996b-059c0885f528.zip |
| Package NDC | Billing unit | Product NDC | DailyMed indexing SPL | SPL version | Effective |
|---|---|---|---|---|---|
| 72603-609-01 | EA - Each | 72603-609 | 24474203-7a0d-4cd8-907e-fa5224fdba2c | 1 | 2025-06-13 |
| 72603-609-02 | EA - Each | 72603-609 | 81cf228e-a973-4f0b-bcec-972e8b37da92 | 1 | 2025-06-13 |
| 72603-610-01 | EA - Each | 72603-610 | 89563f92-46dc-4760-b3dd-9a5b2c11b1fa | 1 | 2025-06-13 |
Chemical name: 5-ethyldihydro-5-phenyl-4,6 (1H, 5H)-pyrimidinedione. Structural formula: Primidone is a white, crystalline, highly stable substance, M.P. 279-284°C. It is poorly soluble in water (60 mg per 100 mL at 37°C) and in most organic solvents. It possesses no acidic properties, in contrast to its barbiturate analog. Primidone Tablets, USP 50 mg and 250 mg contain the following inactive ingredients: lactose monohydrate, NF; magnesium stearate, NF; hypromellose, USP; microcrystalline cellulose, NF; purified water, USP; sodium lauryl sulfate, NF; sodium starch glycolate, NF; and talc, USP/NF. _______________________________________________________________________________
Primidone, used alone or concomitantly with other anticonvulsants, is indicated in the control of grand mal, psychomotor, and focal epileptic seizures. It may control grand mal seizures refractory to other anticonvulsant therapy.
Primidone is contraindicated in: 1) patients with porphyria and 2) patients who are hypersensitive to phenobarbital (see ACTIONS ).
The abrupt withdrawal of antiepileptic medication may precipitate status epilepticus. The therapeutic efficacy of a dosage regimen takes several weeks before it can be assessed.
The total daily dosage should not exceed 2 g. Since primidone tablets therapy generally extends over prolonged periods, a complete blood count and a sequential multiple analysis-12 (SMA-12) test should be made every 6 months.
The most frequently occurring early side effects are ataxia and vertigo. These tend to disappear with continued therapy, or with reduction of initial dosage. Occasionally, the following have been reported: nausea, anorexia, vomiting, fatigue, hyperirritability, emotional disturbances, sexual impotency, diplopia, nystagmus, drowsiness, and morbilliform skin eruptions. Granulocytopenia, agranulocytosis, and red-cell hypoplasia and aplasia, have been reported rarely. These and, occasionally, other persistent or severe side effects may necessitate withdrawal of the drug. Megaloblastic anemia may occur as a rare idiosyncrasy to primidone and to other anticonvulsants. The anemia responds to folic acid without necessity of discontinuing medication. To report SUSPECTED ADVERSE REACTIONS, contact NorthStar Rx LLC, at 1-800-206-7821 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .
Primidone Tablets, USP 50 mg : White to off white, round tablets debossed with ‘Λ’ on one side and scored on the other side in bottles of 100 (NDC 72603-609-01) and 500 (NDC 72603-609-02). 39 250 mg : White to off-white, round, scored tablets debossed with ‘Λ’ above the score line & ‘40’ below the score line on one side and plain on the other side in bottles of 100 (NDC 72603-610-01). Storage Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature]. Dispense in a tight, light-resistant container with a child-resistant closure. Manufactured for: Northstar Rx LLC Memphis, TN 38141. Toll-Free: 1-800-206-7821 Manufactured by: Rubicon Research Ltd., Thane 421506, India. Trademarks are the property of their respective owners. Rev. 01/2025
Primidone (Pri-MI-done) Tablets USP, 50 mg and 250 mg Read this Medication Guide before you start taking primidone and each time you get a refill. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or treatment. What is the most important information I should know about primidone tablets? Like other antiepileptic drugs, primidone may cause suicidal thoughts or actions in a very small number of people, about 1 in 500. Call a healthcare provider right away if you have any of these symptoms, especially if they are new, worse, or worry you: thoughts about suicide or dying attempts to commit suicide new or worsening depression new or worsening anxiety feeling agitated or restless panic attacks trouble sleeping (insomnia) new or worsening irritability acting aggressive, being angry, or violent acting on dangerous impulses an extreme increase in activity and talking (mania) other unusual changes in behavior or mood Do not stop taking primidone tablets without first talking to a healthcare provider. Stopping primidone tablets suddenly can cause serious problems. Stopping a seizure medicine suddenly in a patient who has epilepsy can cause seizures that will not stop (status epilepticus). Suicidal thoughts or actions can be caused by things other than medicines. If you have suicidal thoughts or actions, your healthcare provider may check for other causes. How can I watch for early symptoms of suicidal thoughts and actions? Pay attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings. Keep all follow-up visits with your healthcare provider as scheduled. Call your healthcare provider between visits as needed, especially if you are worried about symptoms. What are primidone tablets? Primidone tablets are prescription medicine used alone or with other medicines to treat people with: generalized tonic-clonic (grand mal) seizures complex partial (psychomotor) seizures partial (focal) epileptic seizures Who should not take primidone tablets? Do not take primidone tablets if you: have a genetic disorder called porphyria are allergic to phenobarbital What should I tell my healthcare provider before taking primidone tablets? Before you take primidone tablets, tell your healthcare provider if you: have or have had depression, mood problems, or suicidal thoughts or behavior have any other medical conditions are pregnant or planning to become pregnant. Primidone may harm your unborn baby. Tell your healthcare provider right away if you become pregnant while taking primidone tablets. You and your healthcare provider will decide if you should take primidone tablets while you are pregnant. If you become pregnant while taking primidone tablets, talk to your healthcare provider about registering with the North American Antiepileptic Drug (NAAED) Pregnancy Registry. You can enroll in this registry by calling 1-888-233-2334. The purpose of this registry is to collect information about the safety of antiepileptic drugs during pregnancy. are breastfeeding or plan to breastfeed. Primidone can pass into breast milk. Talk to your healthcare provider about the best way to feed your baby if you take primidone tablets. Tell your healthcare provider about all the medicines you take, including prescription and nonprescription medicines, vitamins, and herbal supplements. Taking primidone tablets with certain other medicines can cause side effects or affect how well they work. Do not start or stop other medicines without talking to your healthcare provider. Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist each time you get a new medicine. How should I take primidone tablets? Take primidone tablets exactly as prescribed. Your healthcare provider will tell you how much primidone tablets to take and when to take it. Your healthcare provider may change your dose. Do not change your dose without talking to your healthcare provider. Do not stop taking primidone tablets without first talking to your healthcare provider. Stopping primidone tablets suddenly can cause serious problems. If you take too much primidone tablets, call your healthcare provider or local Poison Control Center right away. What should I avoid while taking primidone tablets? Primidone tablets can make you sleepy or dizzy. Do not drink alcohol or take other drugs that make you sleepy or dizzy while taking primidone tablets without first discussing this with your healthcare provider. Taking primidone tablets with alcohol or drugs that cause sleepiness or dizziness may make your sleepiness or dizziness worse. Do not drive, operate heavy machinery, or do other dangerous activities until you know how primidone tablets affects you. Primidone can slow your thinking and motor skills. What are the possible side effects of primidone? See "What is the most important information I should know about primidone?" Primidone may cause other serious side effects including: Sleepiness that can be severe, especially when you first start taking primidone. Primidone may rarely cause blood problems. Symptoms may include: fever, swollen glands, or sore throat that come and go or do not go away frequent infections or an infection that does not go away tiredness shortness of breath Primidone may rarely cause allergic reactions. Symptoms may include: skin rash hives sores in your mouth blistering or peeling skin The most common side effects of Primidone include: problems with walking and moving feelings of dizziness, spinning, or swaying (vertigo) These are not all the possible side effects of Primidone. For more information, ask your healthcare provider or pharmacist. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. How should I store primidone tablets? Store primidone tablets at room temperature between 68º to 77ºF (20º to 25ºC) in a tight, light-resistant container. Keep primidone tablets and all medicines out of reach of children. General Information about primidone tablets Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use primidone tablets for a condition for which it was not prescribed. Do not give primidone tablets to other people, even if they have the same symptoms that you have. It may harm them. This Medication Guide summarizes the most important information about primidone tablets. If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for information about primidone tablets that is written for health professionals. Medication Guide available at http://www.northstarrxllc.com/products or call 1-800-206-7821 What are the ingredients in primidone tablets? Active Ingredient: primidone, USP Inactive Ingredients: lactose monohydrate, NF; magnesium stearate, NF; hypromellose, USP; microcrystalline cellulose, NF; purified water, USP; sodium lauryl sulfate, NF; sodium starch glycolate, NF; and talc, USP/NF. Manufactured for: Northstar Rx LLC Memphis, TN 38141. Toll-Free: 1-800-206-7821 Manufactured by: Rubicon Research Ltd., Thane 421506, India. Trademarks are the property of their respective owners. This Medication Guide has been approved by the U.S. Food and Drug Administration. Rev. 01/2025
Primidone Tablets, USP 50 mg - NDC 72603-609-01 - 100s Bottle Label Primidone Tablets, USP 50 mg - NDC 72603-609-02 - 500s Bottle Label Primidone Tablets, USP 250 mg - NDC 72603-610-01 - 100s Bottle Label