Webster's New World Medical Dictionary

seizure, petit mal
See 
seizure, absence.
seizure, tonic-clonic
The most obvious type of
seizure, which has two parts: the tonic phase (in
which the body becomes rigid) and the clonic phase
(in which there is uncontrolled jerking). Tonic-
clonic seizures may or may not be preceded by
auras, and they are often followed by headache,
confusion, and sleep. They may last for mere sec-
onds or continue for several minutes. If a tonic-
clonic seizure does not resolve or if such seizures
follow each other in rapid succession, the patient
needs emergency help. The patient could be in a
life-threatening state known as status epilepticus.
Also known as grand mal seizure. See also 
status
epilepticus.
seizure disorder
One of a great many medical
conditions that are characterized by episodes of
uncontrolled electrical activity in the brain
(seizures). Some seizure disorders are hereditary,
and others are caused by birth defects or environ-
mental hazards, such as lead poisoning. Seizure dis-
orders are more likely to develop in patients who
have other neurological disorders, psychiatric con-
ditions, or immune system problems than in others.
In some cases, uncontrolled seizures can cause
brain damage, lowered intelligence, and permanent
mental and physical impairment. Diagnosis is made
via observation, neurological examination, elec-
troencephalogram (EEG), and in some cases, more
advanced brain-imaging techniques. Treatment usu-
ally involves use of medication, although in difficult
cases a special diet (ketogenic diet) or brain sur-
gery may be tried. See also 
epilepsy; seizure.
selective estrogen-receptor modulator
A
designer estrogen that can have the ability to both
block and stimulate the actions of estrogen, having
different effects on different body tissues. For exam-
ple, raloxifene (brand name: Evista) prevents bone
loss and lowers serum cholesterol as estrogen does,
but it has been used, like tamoxifen, to block the
action of estrogen on breast cells and is given to pre-
vent breast cancer in some high-risk populations.
Abbreviated SERM. See also 
designer estrogen.