vuls-, vell-

(Latin: to pull, pulling; to tear, tearing, tearing away; to twitch, twitching)

anticonvulsant (adjective) (not comparable)
1. A drug that prevents or relieves convulsions.
2. A reference to a substance or procedure that prevents or reduces the severity of epileptic or other convulsive seizures.
3. Any drug that depresses the central nervous system may be used for its anticonvulsant effect including narcotics and sedatives.

They have the undesirable effect of depressing all central nervous system (CNS) functions.

anticonvulsant (s) (noun), anticonvulsants (pl)
anticonvulsive (adjective) (not comparable)
anticonvulsive (s) (noun), anticonvulsives (pl)
anticonvulsive (s), anticonvulsives (pl) (nouns)
Relieving or preventing convulsion.
clonic convulsion (s) (noun), clonic convulsions (pl)
Relating to abnormal neuromuscular activity characterized by rapidly alternating muscle contraction and relaxation in which the contractions are intermittent and the muscles alternately contracting and relaxing.
complex febrile convulsion (s) (noun), complex febrile convulsions (pl)
A febrile convulsion that is prolonged; that is, longer than fifteen minutes' duratiom or is associated with focal neurological deficits.
convulsant (s) (noun), convulsants (pl)
An agent, such as a drug, that can cause violent involuntary muscle contractions.
convulsant (adjective), more convulsant, most convulsant
Causing or producing convulsions.
convulse (verb), convulses; convulsed; convulsing
1. To shake or to agitate violently: "There were tremors that convulsed the countryside."
2. To affect with irregular and involuntary muscular contractions; such as, to throw into convulsions.
3. To cause to shake with laughter or strong emotion.
4. To move or to stir about violently.
convulsion (kuhn VUHL suhn) (s) (noun), convulsions (pl)
1. A violent shaking of the body or limbs caused by uncontrollable muscle contractions, which can be a symptom of brain disorders and other conditions: Tom had epilepsy which caused moments of convulsions, but with his doctor’s help and medicine, he was able to control the irregular movements of his body.
2. An uncontrolled fit, as of laughter: When Jed tickled his little sister, she couldn’t help herself and was giggling and having convulsions and couldn’t stop!
3. Violent turmoil: The market convulsions of the last year have shaken the global markets and economies.
4. Etymology: from Latin convulsionem, from the past participle stem of convellere, "to tear loose"; from com-, "together" + vellere, "to pluck, to pull violently".
convulsion, revulsion
convulsion (kuhn VUL shuhn) (noun)
A violent or uncontrolled fit often accompanied by violent contractions of muscles: The doctor prescribed medication to control Diana's tendency to have a convulsion when she was anxious.
revulsion (ri VUL shuhn) (noun)
A negative reaction or sudden pulling away from a situation, individual, etc.: Adrienne showed a natural revulsion to the putrid smells in the factory.

When Jean unexpectedly had a convulsion, she threw up. Although Cynthia could understand what happened, her stomach had an instant revulsion to the odor.

convulsive (adjective), more convulsive, most convulsive
A reference to convulsions.
convulsive reflex (s) (noun), convulsive reflexes (pl)
Incoordinate contraction of muscles in a convulsive manner.
convulsive seizure (s) (noun), convulsive seizures (pl)
A sudden onset of a disease, characterized by convulsions, palpitations, and other symptoms which is sometimes applied to an attack of an epileptic disorder.