Primidone can be used alone or in combination with other seizure medications.
Currently, brand-name Mysoline is made by West-ward Pharmaceutical Corp. Generic versions are made by various manufacturers.
In the body, primidone is converted into various other chemicals, including phenobarbital. Phenobarbital is a type of barbiturate that can help control seizures by acting as an anticonvulsant. Unlike primidone, phenobarbital is considered a controlled substance. This means that there are special rules for prescribing and dispensing it (which do not apply to primidone). This is one of the main advantages of this drug. Some people consider it a barbiturate, while others do not.
Epilepsy is a brain disorder caused by recurring, brief changes in the brain's electrical system. These changes in brain activity can lead to a seizure
(see Epilepsy Symptoms). Primidone (and phenobarbital) works by decreasing the excitability of the brain cells. This helps to prevent abnormal electrical activity from starting and keeps such activity from spreading to other parts of the brain.
Some general considerations for when and how to take primidone include the following:
- The medication comes in tablet form and is taken by mouth one to three times daily.
- Primidone can be taken with or without food. If the medication bothers your stomach, try taking it with food.
- Your dosage(s) should be taken at the same time(s) each day to maintain an even level in your blood.
- For the medication to work properly, it must be taken as prescribed. Primidone will not work if you stop taking it. Do not stop taking it without first discussing it with your healthcare provider (see Primidone Withdrawal).
The dose of primidone your healthcare provider recommends will vary, depending on a number of factors, including:
- Your age
- Other medications you may be taking
- Other medical conditions you may have.
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
Side Effects of Primidone
As with any medicine, side effects are possible with primidone. However, not everyone who takes the drug will experience side effects. In fact, most people tolerate it quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
Common side effects include but are not limited to:
- Coordination problems
- A spinning sensation (vertigo)
- Drowsiness.
(Click Side Effects of Primidone to learn more, including potentially serious side effects you should report immediately to your healthcare provider.)
What Should I Tell My Healthcare Provider?
You should talk with your healthcare provider prior to taking primidone if you have:
- Porphyria
- Anemia or any other blood disorder
- Any allergies, including allergies to food, dyes, or preservatives.
Also, let your healthcare provider know if you are:
Make sure to tell your healthcare provider about all of the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
What If I Take an Overdose?
Little information is available regarding what exactly to expect from an overdose with primidone. Based on barbiturate overdoses (which should be similar), people who take too much may have overdose symptoms that could include:
- Drowsiness and fatigue
- A spinning sensation (vertigo)
- Slurred speech
- Coordination problems
- Paranoia (paranoid feelings and thoughts)
- Difficulty breathing
- A rapid heart rate (tachycardia) or slow heart rate (bradycardia)
- Low blood pressure (hypotension)
- Low body temperature (hypothermia)
- Sweating
- Shock
- Coma.
If you happen to take too much, seek immediate medical attention.
How Should Primidone Be Stored?
Primidone should be stored at room temperature, away from moisture and heat. Store the tablets in an airtight container.
Keep this and all medications out of the reach of children.
What Should I Do If I Miss a Dose?
If you do not take your primidone as scheduled, take your missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose. Be aware that if you usually take the drug at bedtime, taking it during the day could cause extreme drowsiness.
Alternatives to Primidone
While primidone is often effective and well tolerated, it does not work for everyone. It may also cause side effects. With so many different treatment options available for treating epilepsy, people should not settle for treatment that is not effective enough for them or that causes bothersome side effects.
Primidone tablets are available in two strengths:
- Primidone 50 mg
- Primidone 250 mg.
Is There a Generic Version of Primidone?
Currently, both brand-name and generic versions of primidone are licensed for sale
(see Generic Mysoline).
