primidone, Mysoline

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Medical Editor:

GENERIC NAME: primidone

BRAND NAME: Mysoline



USES: Primidone is used alone or with other medications for treating grand mal, psychomotor, or focal epileptic seizures. It may be effective for grand mal seizures that are not responsive to other anticonvulsants. Primidone should not be used by patients with porphyria and people who are allergic to phenobarbital.


Common side effects of primidone include:

  • Difficulty speaking (dysarthria)
  • Burning, tingling from damaged nerves (paresthesia)
  • Difficulty moving (ataxia)
  • Loss of balance (vertigo)
  • Paradoxical excitement (children)
  • Hyperactivity (children)
  • Excitement
  • Confusion
  • Depression
  • Drowsiness
  • Irritability
  • Headache
  • Restlessness
  • Nystagmus
  • Dizziness

Possible serious side effects of primidone include:

  • Acute psychosis
  • Nausea
  • Vomiting
  • Constipation
  • Diarrhea
  • Folate-deficiency anemia
  • Liver toxicity
  • Low blood calcium
  • Rickets
  • Weakening of bones
  • Rash
  • Serious skin reactions (for example, Stevens-Johnson syndrome)

Seizure medications increase the risk of suicidal thoughts or behavior. Patients treated with seizure medications should be observed for the emergence or worsening of depression, suicidal thoughts or behavior, and unusual changes in mood or behavior.

Medically Reviewed by a Doctor on 1/21/2016

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