Classification of Anticonvulsants

CLASSIFICATION

1. Barbiturates

2. Hydantoins

3. Oxazolidinedione derivatives

4. Succinimides

5. Phenyl acetyl ureas

6. Benzodiazepines

7. Carbonic anhydrase inhibitors

8. GABA analogues

9. Iminostilbenes

10. Miscellaneous

11. Newer—anticonvulsants

i. Barbiturates

Most of the barbiturates are sedatives and hypnotics. Only a few of them show anticonvulsant characters. Three important barbiturates that show anticonvulsant properties are the following:

ii. Hydantoins

The hydantoins are close structural relatives of barbituric acid, differing due to the lack of C-6 oxo group. The lack of this carbonyl group decreases the acidity. So it is a weaker acid than that of barbiturates.

iii. Oxazolidinediones

Replacement of the -NH group at position 1 of the hydantoin systems with oxygen atom yields the oxazolidine-2,4-dione system, trimethadione is only clinically used.

IV. Succinimides

V. Acetyl urea derivatives or phenyl acetyl ureas

VI. Benzodiazepines

VII. Carbonic anhydrase inhibitors

VIII. Gamma amino butyric acid (GABA) analogues

IX. Iminostilbenes

X. Miscellaneous

XI .Newer anticonvulsants

Drugs used for treating epileptic disorders are listed in Table 9.1

Table 9.1 Drugs used for treating epileptic disorders.

Pharmalocogical Classification

Anticonvulsant drugs can be classified as follows:

• Centrally acting: General anaesthetics, paraldehyde, barbiturates, and diazepam.

• Acting mainly on the spinal cord: Mephenesin.

• Peripheral skeletal muscle relaxants: d-Tubocurarine and succinyl choline.