www . specialistforum . co . za
NEUROLOGY
Epilepsy and seizures : treatment and management
The goal of treatment in patients with epileptic seizures is to achieve a seizurefree status without adverse effects .
Mechanisms of action
» Blockers of repetitive activation of the sodium channel
» Enhancers of slow inactivation of the sodium channel
» Gamma-aminobutyric acid ( GABA ) -A receptor enhancers
» N -methyl-D-aspartic acid ( NMDA ) receptor blockers
» Alpha-amino-3-hydroxy- 5-methyl-4-isoxazole propionic acid ( AMPA ) receptor blockers
» T-calcium channel blockers
» N- and L-calcium channel blockers
» H-current modulators
» Blockers of unique binding sites
» Carbonic anhydrase inhibitors
» Neuronal potassium channel ( KCNQ [ Kv7 ]) openers
The goal of achieving a seizure-free status in patients is accomplished in more than 60 % of patients who require treatment with anticonvulsants . Many patients experience adverse effects from these drugs , however , and some patients have seizures that are refractory to medical therapy .
Epilepsy defined
Epilepsy is a chronic disorder , the hallmark of which is recurrent , unprovoked seizures . Many people with epilepsy have more than one type of seizure and may have other symptoms of neurological problems as well .
Sometimes EEG testing , clinical history , family history and outlook are similar among a group of people with epilepsy . In these situations , their condition can be defined as a specific epilepsy syndrome .
The human brain is the source of human epilepsy . Although the symptoms of a seizure may affect any part of the body , the electrical events that produce the symptoms occur in the brain . The location of that event , how it spreads and how much of the brain is affected , and how long it lasts all have profound effects . These factors determine the character of a seizure and its impact on the individual . Essentially , anything the brain can do , it can do in the form of a seizure .
Having seizures and epilepsy can affect one ’ s safety , relationships , work , driving and so much more . Public perception and treatment of people with epilepsy are often bigger problems than actual seizures .
A person is diagnosed with epilepsy if they have one or more seizures that were not caused by some known and reversible medical condition like alcohol withdrawal or extremely low blood sugar . The seizures in epilepsy may be related to a brain injury or a family tendency , but often the cause is completely unknown . The word epilepsy does not indicate anything about the cause of the person ’ s seizures or their severity .
Treatment and management
A recent study by David Y Ko , MD Associate Professor of Clinical Neurology , Associate Director ,
USC Adult Epilepsy Program , Keck School of Medicine of the University of Southern California , highlights the desirability of monotherapy .
According to the authors , “ Monotherapy is desirable because it decreases the likelihood of adverse effects and avoids drug interactions . In addition , monotherapy may be less expensive than polytherapy , as many of the older anticonvulsant agents have hepatic enzymeinducing properties that decrease the serum level of the concomitant drug , thereby increasing the required dose of the concomitant drug .”
People with seizures experience psychosocial adjustments after their diagnosis ; therefore , social and / or vocational rehabilitation may be needed . Many physicians underestimate the consequences that an epilepsy diagnosis may have on patients .
“ For example , patients with epilepsy may live in fear of experiencing the next seizure , and they may be unable to drive or work at heights ,” states Ko .
Refer patients with intractable spells to a neurologist or an epileptologist for further workup , including video-electroencephalographic ( EEG ) monitoring , to characterise the etiology of their seizures . A neurosurgical consult is recommended when the possibility of surgical management is considered .
Recurrence risk
For patients who have had more than one unprovoked seizure , treatment with an anticonvulsant is recommended , states the study .
“ However , the standard of care for a single unprovoked seizure is avoidance of typical precipitants ( e . g ., alcohol , sleep deprivation ); anticonvulsants are not recommended unless the patient has risk factors for recurrence .”
The risk of recurrence in the two years after a first unprovoked seizure is 15-70 %. Principal factors that increase the risk of recurrence are an abnormal brain magnetic resonance image ( MRI ) study , an abnormal electroencephalogram ( EEG ), and a partial-onset seizure .
“ On brain magnetic resonance imaging ( MRI ), a focal abnormality in the cortical or limbic regions that indicates a possible substrate
32 | May 2017
The Specialist Forum | Vol . 17 No . 4