Nervous System Home > Side Effects of Phenytoin
Some of the most common side effects of phenytoin seen in clinical studies include slurred speech, muscle coordination problems, unusual eye movements, and confusion. While most phenytoin side effects are minor and don't require medical attention, some are potentially serious and should be reported to a healthcare provider right away. Notify your healthcare provider if you develop worsening seizures, unusual behavior or thinking, or high blood sugar, among other serious side effects.
- Unusual eye movements
- Muscle coordination problems
- Slurred speech
- Insomnia (see Dilantin and Insomnia)
- Nausea, vomiting, or constipation
- Larger or fuller lips
- Problems with the gums (including swelling, tenderness, and unusual growth)
- Excessive body or facial hair.