Drugs are the most widely used treatment for epilepsy. If you have seizures, you have almost certainly been treated with drugs at some point in your life. Your experience may have ranged from very good to terrible. There are wonderful stories of people whose seizures are perfectly controlled by medications, allowing them to participate in any activity they desire including driving a car .
On the other hand, there are horror stories of individuals who have suffered severe side effects, or have actually dies, after taking an anticonvulsant.
Many drugs are presently in use against epilepsy. They work through various mechanism, and not all of them work against all types of seizures, but when they are used correctly they are good drugs, and can be of tremendous benefit.
Some of them are designed to suppress seizures by preventing the spread of abnormal electrical activity from the focus to other parts of the brain. Others are targeted toward preventing the spread of electrical excitation from one brain cell to another. To achieve this, they may act on the excitatory neurotransmitters, or they may enhance or mimic the inhibitory neurotransmitters.
However, most drugs work on the surface of brain cells, to block electrical activity along the individual cells. Here are some of them:
Phenobarbital is a landmark drug. It was the first real anticonvulsant ever discovered, and it has been used for more than any other drug in the treatment of epilepsy. Even today, on a world wide basis, it is the most widely used anticonvulsant drug, especially in developing countries.
Primidone Like phenobarbital, primidone has been around for a very long time. In fact, the two drugs are closely related and form a chemical perspective the primidone molecule is quite similar to the phenobarbital molecule. However, these are not identical drugs. Primidone itself has anticonvulsant activity, and it is converted by the body to phenobarbital and to another chemical called phenylethylmalonamide.
Phenytoin has a long history. It was first evaluated as a sleeping pill, but was found to have anticonvulsant effects as well. Phenytoin does not work on all seizure types. It tends to work better on secondary epilepsies. Thus it works best for tonic clonic seizures and partial seizures.
Ethosuximide It bears a certain resemblance to phenytoin, but it’s only effective against absence seizures. It doesn’t work on any of the secondary epilepsies, or against simple partial or complex partial seizures, and it has no effect on epilepsies that begin in adulthood.
Carbamazepine is probably one of the most widely used anticonvulsants. It too was discovered more by accident than by design. It was initially used as an antidepresant, but it soon became clear that the drug’s anticonvulsant properties were much more marked, and it is nor used mainly for these properties.
Valproic Acid is structuarraly uniwue, and its properties and toxicities are different from those of other anticonvulsants. Vaproic acid can cause weight gain, hair loss and tremor, but generally will less confusion and fatigue than are associated with the other drugs. Also, valproic acid is a broad spectrum anticonvulsant.
Clonazepam together with nitrazepam and diazepam, belongs to a largerfamily of drugs called 1,4 benzodiazepines. Many drugs within this family are used as sleeping agents or to reduce anxiety. They are sometimes used to prevent alcoholic in withdrawal from experiencing the “DTs”
Clobazam is a 1.5 benzodiazepine. This subtle chemical distinction means fewer problems with developent of tolerance to the anticonvulsant action than there are with clonazepam. For this reason, clobazam is probably the benzodiazepine of choice in the treatment of seizures at the present time.
Vigabatrin The appearance of vigabatrin heralded a new era of anticonvulsants drug in the 1980s in Europe and 1990 in Canada. Vigabitrin has not been approved in USA. Unlike the earlier anticonvulsants, vigabatrin wan not stumbled upon by accident.
Gabapentin Like vigabatrin, gabapentin was designed and created, not discovered accidentally. A growing body of evidence suggests that, beyond its anticonvulsant properties, it may be useful in the treatment of pain disorders, especially the neuralgias associated with diabetes and shingles.
Lamotrigine is an extremely effective new anticonvulsant. It too is a product of drug design, however, the chemist who created it were testing a theory that turned out to be wrong. Lamotrigine works well at suppressing seizures, but the mechanism that makes it effective is not the one its designers were investigating. So its discovered was deliberate but also accidental.