The brain serves as the control center for the body, sending and receiving electrical impulses throughout the body. A disruption in these electrical impulses causes brain dysfunction known as a seizure. Doctors diagnose a seizure disorder as epilepsy, a neurological condition, when a patient experiences two or more unprovoked seizures, according to the Epilepsy Foundation. Although epilepsy cannot be cured, doctors prescribe drugs known as anticonvulsant medications to reduce the severity and frequency of seizures. They type of anticonvulsant used for treatment depends upon the type of seizure and the side effects felt by each patient.
Gabapentin
Gabapentin decreases abnormal electrical activity in the brain therefore decreasing the incidence of seizures in those with epilepsy. Available as a capsule, tablet or oral suspension, patients take gabapentin orally. Because gabapentin affects the brain activity it can cause anxiety, vision impairments, memory problems, strange thoughts and unwanted eye movements. Other side effects include drowsiness, weakness, dizziness, headache and joint pain. Gabapentin can also cause stomach upset characterized by nausea, vomiting, diarrhea, constipation, heartburn, dry mouth and weight gain.
Carbamazepine
Like gabapentin, carbamazepine reduces the electrical activity in the brain therefore affecting epilepsy. Because patients take this medication orally as a tablet, capsule or liquid, it can cause stomach upset such as nausea, vomiting, diarrhea, constipation and heartburn. The most common symptoms, according to MayoClinic.com, include blurred vision and rapid, continuous eye movements. Some patients may experience a life-threatening allergic reaction known as Stevens-Johnson syndrome or toxic epidermal necrolysis causing severe skin and internal organ damage, according to MedLine Plus and the U.S. National Library of Medicine.
Lamotrigine
Doctors prescribe lamotrigine to treat the seizure disorders of epilepsy and Lennox-Gastaut syndrome---a severe form of epilepsy. As with other anticonvulsant medications lamotrigine reduces the electrical activity in the brain. The effects on the brain include a loss of balance, dizziness, drowsiness, irritability, nervousness, mood changes, sleep disturbances, blurred vision and double vision. Digestive side effects include stomach pain, vomiting, diarrhea, heartburn and constipation. MedLine Plus and the U.S. National Library of Medicine reports that lamotrigine can cause serious rashes, especially when taken in combination with other anticonvulsant medications such as valproic acid.
Valproic Acid
Valproic acid may increase the level of gamma-aminobutyric acid, a neurotransmitter that decreases the activity of other neurotransmitters in the brain, therefore decreasing electrical activity. Doctors utilize valproic acid, either alone or in combination with other anticonvulsant drugs, to treat simple and complex absence seizures as well as myoclonic atonic seizures, according to Inchem.org. Valproic acid may cause serious damage to the liver and pancreas which can cause digestive disturbances leading to stomach pain, nausea, vomiting and loss of appetite. Other side effects resemble those from other anticonvulsants including drowsiness, dizziness, headache, shaking, loss of coordination, blurred vision and memory loss.
