Seizure medications are generally safe, but side effects can, and do, occur. Their degree of severity depends on the kind of medication being taken, the dosage, and the individual response of a patient to that medication.
Minor side effects are not uncommon at the beginning of medication therapy, but an allergic reaction is a severe adverse condition that necessitates an immediate change to another medication.
Side effects are sometimes related to the level of the medication in the blood. These side effects are referred to as dose-related and can include drowsiness, loss of coordination, fatigue, headache, decreased appetite, nausea, drooling, tremor, weight gain or loss, double or blurred vision, dizziness, and impaired attention and memory. Sometimes dose-related side effects are cosmetic and include overgrowth of the gums, hair loss, or excessive hair growth.
Allergic side effects are less common and may include skin rash or reactions that may affect the liver, blood cells, or bone marrow. Skin rash may often be the first sign of an allergic reaction to a medication. These reactions require immediate medical attention.
Chronic side effects are those developed after using medication for long periods. These may include loss of bone density (osteoporosis), weight gain, hair loss, loss of balance, and cognitive impairment.
Despite these problems, many people are able to take their medication for years without experiencing any side effects. When side effects do occur, they should be reported to a treating physician withot delay.