Primidone is a prescription anticonvulsant medication used to decrease certain electrical impulses in the brain that can lead to seizures. The medication is often very effective at decreasing seizures, but it can cause many different side effects, some of which are potentially very dangerous. It is extremely important for patients who take primidone to tell their doctors about any side effects they experience and disclose any medications they currently take to prevent serious drug interactions.
Patients on primidone typically take the medication three or four times a day to keep a steady supply of the drug in their bloodstreams to control seizures. Due to the potential side effects of the medication, doctors usually start seizure patients on a low dose of the drug and gradually increase the amount of each dose until the patient's seizures are adequately controlled. If a patient needs to come off primidone due to side effects or if switching to another medication, the dose is usually gradually reduced to reduce the risk of worsening seizures and withdrawal symptoms, including insomnia, anxiety, and hallucinations.
The most common side effects of primidone are drowsiness, loss of appetite, nausea, vomiting, dizziness, and mild vision changes. Many of these side effects subside once the patient develops a tolerance for the medication. The side effects are usually mild, but patients experiencing severe symptoms should consult with their doctors. Primidone can be harmful to an unborn baby, so pregnant women and those trying to conceive should not take the drug. The medication can also lower the effectiveness of birth control pills and other forms of hormonal contraceptive, so women of child-bearing age should consult with their doctors about alternative birth control methods while taking primidone.
Changes in mood and mental health problems are a large concern for patients on anticonvulsants. Some patients may develop symptoms of depression. In severe cases, these mental health changes lead to suicidal thoughts or actions. Patients should talk to their doctors immediately about any mood or behavior changes that occur when taking this drug or any other anticonvulsant medication.
Serious side effects and allergic reactions to this drug are rare, but they require emergency medical attention if experienced after taking primidone. Slow heart rate, difficulty breathing, fainting, and severe weakness are potentially serious complications that occur in a small number of patients. The most common signs of an allergic reaction are rash, swelling of the face or mouth, and severe dizziness.