 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  your phenytoin dose, or as directed by your doctor. Do not stop taking this medication without consulting your doctor. Seizures may become worse when the drug is suddenly stopped. Your dose may need to be gradually decreased. Inform your doctor if your condition does not improve or worsens.The side effects of Dilantin Kapseal Oral: Headache, nausea, vomiting, constipation, dizziness, feeling of spinning, drowsiness, trouble sleeping, or nervousness may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Phenytoin may cause swelling and bleeding of the gums. Massage your gums and brush and floss your teeth regularly to minimize this problem. See your dentist regularly. Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: slow heartbeat, unusual eye movements, loss of coordination, trouble speaking, confusion, muscle twitching, double/blurred vision, tingling of the hands/feet, facial changes (such as swollen lips, butterfly- </s>