What Anticonvulsants Affect GABA Levels?

GABA is one of many neurotransmitters essential to the healthy functioning of the brain. It is an inhibitory neurotransmitter that controls nerve impulses. Seizures happen when there is too much neuronal activity in the brain. Too little GABA in the brain causes nerve cells to fire too frequently and easily. So many anticonvulsants work to increase GABA levels in the brain which make neurons less active, providing an anti-epileptic effect.

Benzodiazepines

• Benzodiazepines work by enhancing the effect of GABA. Valium, Librium, Klonopin and Ativan are the benzodiazepines used most often for the treatment of seizure disorders. Valium and Ativan are fast-acting and are thus first choices in emergency situations. Librium and Klonopin are sometimes chosen for the long-term treatment of seizure disorders; but because of their side effects, which include drowsiness and dependence, these are not first line choices.

GABA Analogues

• GABA analogues are drugs that have a chemical composition very near to GABA. They bind to GABA receptors and initiate a calming response. Drugs, such as Gabapentin, commonly sold as Neurotonin, and Pregabalin, branded as Lyrica, are GABA analogues.

Barbituates

• Phenobarbital was one of the first widely available anticonvulsant medications. It is widely used even today. Barbituates, such as phenobarbital, bind to GABA receptors and enhance the effects of the neurotransmitter. Other powerful anticonvulsants, such as Primidone, have, as their active metabolites, phenobarbital. Phenobarbital has a heavy sedative effect and has a high potential for overdose. Therefore, it is rarely a first choice for the treatment of seizure disorders.

Valproates

• Valproates include drugs, such as Depakote, that work by inhibiting GABA transaminase, which aids in the breakdown of the amino acids that form GABA. By doing this, it increases the concentration of GABA in the brain. Valproates are effective anticonvulsants but have a tendency to cause weight gain. They are also known to cause birth defects during pregnancy, so women who intend to get pregnant should avoid this type of anticonvulsant.