Most people who take Dilantin don't have too much trouble with side effects. That's one of the reasons it's used so much. The most common complaints (usually not too severe) are:
If these problems do not go away within several days, or are really bothersome, call the doctor. Most people get over these side effects without a change in the amount of Dilantin they're taking. But if the side effects persist, it is usually a sign that the level of medication in the body is too high. A change in the dose or type of Dilantin may help. No one should stop taking Dilantin or change the amount they take without their doctor's guidance, however.
People who have just started taking Dilantin (or who have just started taking a larger amount) should be careful during activities that might be dangerous, until they know whether they are having any side effects.
Approximately 1 in 10 people who take Dilantin have a red rash within the first few weeks of taking it. If this happens, tell the doctor or nurse right away, to be sure that it's not the beginning of a serious problem. It's rare for the rash to be serious, but don't ignore it. It's often necessary to switch to a different seizure medicine.
Long-term side effects
Some other side effects only appear after a person has been using Dilantin for a number of months or years. They are usually related to taking high doses. The most common ones affect appearance:
Overgrowth of the gums (gingival hyperplasia) is more common in children than in adults. It can be reduced by vigorous brushing, daily flossing, and regular visits to the dentist, who may recommend additional treatments. If Dilantin is stopped, the gum problems won't get worse, and in some cases will go away within a few months.
Long-term use of Dilantin also has been found to cause weakening of the bones. Bone disease is even more likely if a combination of seizure medicines is used. People taking Dilantin should exercise, take vitamin D supplements, and eat foods rich in calcium. Some non-food sources of calcium, such as Tums and Os-Cal, reduce absorption of Dilantin. They can be used but should not be taken within about 2 hours after taking the Dilantin.
Some people who take Dilantin for several years may have damage to the nerves in their legs. Faulty reflexes can be seen in a minority of this group.
Damage to the part of the brain called the cerebellum may affect others who take Dilantin for a long time, especially if they take high doses. Damage severe enough to produce significant problems is uncommon, however.
This content is user-generated. Content is not monitored nor consistently reviewed by the epilepsy.com Editorial Board. Epilepsy.com therefore cannot guarantee the accuracy of any content edited with the Wiki sections. While epilepsy.com, the Epilepsy Therapy Project, and its partners encourage visitor interaction and publishing within these sections, users should use caution when exploring content, especially as it pertains to health concerns. No content on epilepsy.com is intended to replace the care of a doctor. We encourage you to contact your own health care provider for individual medical advice. We cannot provide second opinions or make specific recommendations regarding therapy, nor does this Wiki content constitute a recommendation for any diagnosis or treatment options.
Dilantin is prescribed for epilepsy and for depression. Side effects are ALSO, tooth decay (because of gum overgrowth which keeps the average tooth brush and brusher from accessing the tooth enamel under the gums). Once gums recede even a weensy bit, tooth decay starts. Once decay starts, references say that ceasing Dilantin stops the decay already present, but the decay already present is not on the chewing part of the teeth, but rather, on the part of the tooth at the gum line. Teeth need to be pulled; bridges need to be built and worn. Dilantin's destruction of the gums, and of the bone density that hold the gums and teeth, make most dentists who would have, before, suggested dental implants, decide NOT to implant anything in already distressed bones and gums around and under the teeth. People who are epileptic then have to turn to wearing removeable dental appliances. Choose another medication if such a med exists to stop your kind of seizures.