<span>&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;</span><p></p><p>Anti-epileptic drugs (AED) and anti-convulsant drugs are most prescribed by neurologists for the treatment of seizures and epileptiform discharges.</p><p></p><h2>Negative/Bad Effects of AED Drugs on EEG</h2>

<p><!--[if !supportLists]-->-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Diffuse Slowing</p>

<p><!--[if !supportLists]-->-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Electro-cerebral Inactivity</p>

<p><!--[if !supportLists]-->-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Epileptiform Discharges (this is rare)</p>

<h3>Drugs that cause this:</h3>

<p><!--[if !supportLists]-->·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Phenobarbital</p>

<p><!--[if !supportLists]-->·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Benzodiazepines</p>

<p><!--[if !supportLists]-->·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Carbamazepine</p>

<p><!--[if !supportLists]-->·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Phenytoin</p>

<p><!--[if !supportLists]-->·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->Ethosuximide</p>

<h2><a name="_Toc14686148">Positive/Good Effects of AED Drugs on EEG</a></h2>

<p><!--[if !supportLists]-->-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->In epilepsy, reduction in generalized Spike and
Wave (classic epileptiform EEG)</p>

<p><!--[if !supportLists]-->-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<!--[endif]-->In epilepsy, decreased reactivity to
photoparoxysms with photic stimulation</p>

<h2>Other Effects of AEDs:</h2>

<p><!--[if !supportLists]-->o&nbsp;&nbsp;
<!--[endif]-->May reduce alpha frequency and voltage<u></u></p>

<p><!--[if !supportLists]-->o&nbsp;&nbsp;
<!--[endif]-->Diffuse slowing and depressed levels of
consciousness<u></u></p>

<p><!--[if !supportLists]-->o&nbsp;&nbsp;
<!--[endif]-->Toxicity produces higher amplitude beta spindles<u>&nbsp;(t</u><span style="font-size: 1rem;">his includes anything that induces sleep, anything ending in “azepam” or
“albetol”)</span></p><p><u></u></p>

<p>Some types of anti-epileptic drugs for focal
epileptiform discharges can cause seizures, agents that are gabaergic can
induce absence or myoclonic epilepsy.</p><p></p><h1>Generic AED names with&nbsp;brand names</h1><h4>Carbamazepine&nbsp;also available as&nbsp;Carbagen,&nbsp;Tegretol,&nbsp;Tegretol Prolonged Release</h4><p><br></p><h3>Image of Tegretol pills and chemical bond</h3><p><img src="@@PLUGINFILE@@/Carbamazepine%20%281%29.jpg" alt="Carbamazepine" width="500" height="726" class="img-responsive atto_image_button_left"><br></p><p>Carbamazepine is a favorite partial seizure medicine in the developed world. Carbamazepine affects sodium channels, and inhibits rapid firing of brain cells. Long-acting forms such as Carbatrol or Tegretol-XR can be given once a day. Potential side effects include gastero-intestinal upset, weight gain, blurred vision, low blood counts, and low blood sodium (hyponatremia). Carbamazepine causes a rash rate of a few percent, sometimes even the dangerous rash called Stevens-Johnson syndrome. People of Asian descent with HLA-B*1502 antigen are more at risk. Typical adult dose is 400 mg tid.&nbsp;</p><p>This is a good choice of AED for slow alpha variants.</p><br><p></p><p><br></p><p><br></p><p><br></p><p><br></p><p><br></p><p><br></p><h4><br></h4><h4><br></h4><h4><br></h4><h4><br></h4><h4><br></h4><h4><br></h4><h4>Benzodiazepines and EEG Effects</h4><p>Benzodiazepines produce a spindling, sinusoidal hyper-rhythmic 18-25Hz pattern. They also decrease alpha.&nbsp;<span>Sometimes this pattern is more pronounced in the front of the head, but the pattern can be seen globally.&nbsp;</span><span>Dosing and systemic vascularity of the being will alter the expression of how the drug will appear.</span></p><p style="text-align: center; "><span><audio controls="true" class=""><source src="@@PLUGINFILE@@/9796486011639889-audio.ogg">@@PLUGINFILE@@/9796486011639889-audio.ogg</audio><br></span></p><p style="text-align: center; "><span><br></span></p><p style="text-align: center; "><span><a href="@@PLUGINFILE@@/Benzodiazepine%20EEG.mp4">Benzodiazepine EEG.mp4</a><br></span></p><p><br></p><h3><span>&nbsp;Image of Benzodiazepine Pill Abuse Statistics</span></h3><h4><p style="text-align: center;"><span style="font-size: 1.286rem;">&nbsp;</span><img src="@@PLUGINFILE@@/Benzodiazepine%20Abuse%20Statistics.png" alt="Benzodiazepine Abuse Statistics" width="600" height="331" class="atto_image_button_middle" style="font-size: 1.286rem; text-align: center;"></p><p style="text-align: center;"><br></p></h4><p><br></p><p><br></p><h4><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.715rem;">Image of Different Types of Benzodiazepine Pills</span></h4><p style="text-align: center; ">&nbsp;<img src="@@PLUGINFILE@@/Benzodiazepine%20Pills.jpg" alt="Benzodiazepine Pills" width="600" height="291" style="text-align: center; " class="img-responsive atto_image_button_middle"></p><p style="text-align: center;"><br></p><h4><span style="font-size: 1.286rem;"><br></span></h4><h4><span style="font-size: 1.286rem;">Image of Benzodiazepine Toxicity in EEG</span><br></h4><p style="text-align: center; "><img src="@@PLUGINFILE@@/Benzodiazepines%20in%20the%20EEG.png" alt="Benzodiazepines in the EEG" width="700" height="624" class="img-responsive atto_image_button_middle"></p><p style="text-align: center; ">·&nbsp; &nbsp; &nbsp;&nbsp;</p><h4>Image of Benzodiazepine Toxicity in a Linked Ears Montage. <i>Image generated from Neuroguide version 3.0.6.</i></h4><p style="text-align: center; "><img src="@@PLUGINFILE@@/BENZODIAZEPINE%20QEEG.png" alt="BENZODIAZEPINE QEEG" width="700" height="906" class="img-responsive atto_image_button_middle"><br></p><p></p><p>·&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</p><p></p><h3><span style="font-size: 1.286rem;">Image of Benzodiazepine Toxicity in individual Hertz bins (linked ears montage). </span><i style="font-size: 1.286rem;">Image generated from Neuroguide version 3.0.6.</i><br></h3><p style="text-align: center;"><img src="@@PLUGINFILE@@/Benzodiazepines%20in%20individual%20hertz%20bins.png" alt="Benzodiazepines in individual hertz bins" width="700" height="354" class="atto_image_button_middle"><br></p><p style="text-align: center;"><br></p><p style="text-align: center;"><br></p><p style="text-align: center; "><img src="@@PLUGINFILE@@/Benzodiazepines%20in%20individual%20hertz%20bins2.png" alt="Benzodiazepines in individual hertz bins" width="700" height="351" class="img-responsive atto_image_button_text-bottom"><br></p><p style="text-align: center; "><br></p><p style="text-align: center; "><br></p><h3>More Anti-Convulstants</h3><h4><br></h4><p><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.715rem;"><img src="@@PLUGINFILE@@/Neurontin.jpg" alt="Neurontin Pills" width="400" height="290" class="img-responsive atto_image_button_left"><br></span></p><p></p><p></p><h4>Gabapentin&nbsp;also available as&nbsp;Neurontin</h4><p></p><p>This is often used as a secondary anticonvulsant to boost GABA.&nbsp;Gabapentin has the reputation of being a safe but not particularly powerful AED. The effectiveness criticism probably is because it is often prescribed at too low a dose. The drug probably works by influencing transport of GABA and effects on calcium channels. It has no drug interactions, is not metabolized in the liver and it does not bind to blood proteins. Side effects are unsteadiness, weight gain, fatigue, dizziness. Typical adult dose is 300-600 mg three times a day, but doses can be up to 1200 mg three times a day.</p><p><br></p><p><br></p><h4 style="text-align: center;"><br></h4><h5><img src="@@PLUGINFILE@@/Vimpat.jpg" alt="Vimpat" width="401" height="267" class="img-responsive atto_image_button_left"><span style="font-size: 1rem;"><h4><a href="https://www.medicines.org.uk/emc/search?q=lacosamide" target="_blank">Lacosamide</a><span>&nbsp;available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=lacosamide" target="_blank">Vimpat</a>&nbsp; &nbsp; &nbsp; &nbsp;</h4></span></h5><p>Lacosamide is a new (2009) antiepileptic drug, for partial and secondarily generalized seizures. It is chemically related to the amino acid, serine. Vimpat blocks sodium channels (but in a different way from other seizure medicines), and this block reduces brain excitability. Side effects include dizziness, headache, nausea or vomiting, double vision, fatigue, memory or mood problems. Vimpat may affect the internal organs, blood counts or heart rhythm, but these potentially serious side effects are infrequent. The recommended starting dose is 50 mg twice daily, increased each week by an extra 100 mg, to the recommended maintenance dosage of 100-200 mg 2x/day.&nbsp; &nbsp;</p><p><br></p><p><br></p><p><br></p><p><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.286rem;"><img src="@@PLUGINFILE@@/Lamictal.jpeg" alt="Lamictal" width="400" height="300" class="atto_image_button_left"></span></p><h4><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.286rem;">&nbsp;</span><a href="https://www.epilepsysociety.org.uk/lamotrigine" style="font-family: &quot;Open Sans&quot;; font-size: 1.286rem; background-color: rgb(255, 255, 255);">Lamotrigine</a><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.286rem;">&nbsp;also available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=Lamotrigine" target="_blank" style="font-family: &quot;Open Sans&quot;; font-size: 1.286rem; background-color: rgb(255, 255, 255);">Lamitcal</a></h4><p></p><p>Lamotrigine is a broad-spectrum alternative to VPA, with a better side effect profile. However, lamotrigine may not be as effective for myoclonic seizures. Lamotrigine works by several mechanisms including blocking release of glutamate, the brain’s main excitatory neurotransmitter. It has the usual side effects of dizziness and fatigue, usually mild cognitive (thinking) impairment. Severe medical side effects are unusual. The practical side effect issue is rash, occurring in several percent of people who take it, especially if the dose is increased too fast. Therefore, it takes a couple of months to get up to the typical adult dose of 200 mg twice a day.&nbsp;</p><p>This is the best option for an EEG when the individual has a normal peak frequency alpha.</p><p><br></p><p><br></p><p><br></p><h4></h4><p></p><p><img src="https://schoolofneurotherapy.com/classroom/pluginfile.php/472/mod_lesson/page_contents/357/Keppra.jpg" alt="Keppra" width="300" height="200" class="img-responsive atto_image_button_left"></p><h4><a href="https://www.epilepsysociety.org.uk/levetiracetam" style="font-size: 1.286rem; background-color: rgb(255, 255, 255);">Levetiracetam</a><span style="font-size: 1.286rem;">&nbsp;also available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=%22Levetiracetam%22" target="_blank" style="font-size: 1.286rem; background-color: rgb(255, 255, 255);">Desitrend</a><span style="font-size: 1.286rem;">,&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=%22Levetiracetam%22" target="_blank" style="font-size: 1.286rem; background-color: rgb(255, 255, 255);">Keppra</a><br></h4><p>Levetiracetam is one of the more used medicines in seizure clinics because it probably is effective for a broad-spectrum of seizures types, has a relatively low incidence of causing thinking/memory problems, and can be started at 500 mg twice a day, which is an effective dose. It has no drug interactions, is not metabolized in the liver and it does not bind to blood proteins. The most common side effects are dizziness, fatigue, insomnia, but the more troublesome problem can be irritability and mood changes. This may occur to some degree in up to a third of those taking the medicine. A typical adult dose is 500 - 1500 mg twice a day. This is best for epileptic findings that are temporal and generalized.<br></p><p><br></p><p><img src="@@PLUGINFILE@@/Ativan.jpg" alt="Ativan" width="400" height="300" class="atto_image_button_left"></p><h4>Lorazepam (Ativan)</h4>Lorazepam is similar to clonazepam in dosage and action, but it is not as long-acting. It is usually used as a ‘rescue medication’ for patients who frequently have clusters of seizures. Best used&nbsp;for status epilepticus or very short-term management, as it is highly addictive and has dependency&nbsp;potential.&nbsp;It works reasonably quickly when taken orally and anti-seizure effect lasts for 2-6 hours. Typical adult dose is 0.5-2.0 mg orally or as needed.&nbsp;<p></p><h4><br></h4><p><br></p><p><br></p><p><br></p><p><br></p><h3><img src="@@PLUGINFILE@@/Oxcarbmazepine.jpg" alt="Oxcarbazepine" width="400" height="300" role="presentation" class="atto_image_button_left"></h3><h4><a href="https://www.medicines.org.uk/emc/search?q=%22Oxcarbazepine%22" target="_blank">Oxcarbazepine</a><span>&nbsp;also available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=%22Oxcarbazepine%22" target="_blank">Trileptal</a><span>&nbsp; &nbsp;&nbsp;</span></h4><p>Slightly different from carbamazepine, it is at least as effective and may have fewer side effects, except for more risk for low blood sodium (hyponatremia). It is more expensive than generic carbamazepine. A typical adult dose is 600 mg twice a day. Ideal for people with slow alpha peak frequencies.&nbsp; &nbsp;&nbsp;<br></p><p><br></p><p><br></p><p><br></p><p><br></p><h4><br></h4><h4><br></h4><p><img src="@@PLUGINFILE@@/Phenobarbitol.jpg" alt="Phenobarbitol" width="401" height="300" class="img-responsive atto_image_button_left"><br></p><p></p><h4><a href="https://www.medicines.org.uk/emc/search?q=%22Phenobarbital%22" target="_blank">Phenobarbital</a>&nbsp;also available as Luminal</h4>The old-timer: very inexpensive and effective in a single daily dose. Phenobarbital increases the effect of GABA, the main inhibitory neurotransmitter in the brain. Watch for sedation, thinking/memory problems and depression. Phenobarbital can cause long-term bone problems. Phenobarbital is mildly addictive and requires slow withdrawal. Phenobarbitol is used for infants.<p></p><h3><br></h3><p><br></p><h4>&nbsp;</h4><h4><br></h4><p><img src="@@PLUGINFILE@@/dilantin.jpg" alt="Dilantin" width="300" height="300" class="img-responsive atto_image_button_left"></p><h4><a href="https://www.epilepsysociety.org.uk/phenytoin">Phenytoin</a>&nbsp;also available as<a href="https://www.medicines.org.uk/emc/search?q=phenytoin" target="_blank">&nbsp;Epanutin</a>,&nbsp;<a href="https://www.medicines.org.uk/emc/search?q=phenytoin+sodium+flynn" target="_blank">Phenytoin Sodium Flynn</a>, Dilantin</h4><p></p><p>The most used AED by general physicians in the US, less so by epilepsy doctors, because of the side effects. Phenytoin alters brain cell sodium channels, which has the effect of limiting&nbsp;rapid firing of the brain cells. It is inexpensive. Common side effects are unsteadiness and moderate cognitive problems. There are long-term potential cosmetic (body/face hair growth, skin problems), and bone problems (osteoporosis). Phenytoin causes a rash rate of a few percent, sometimes even the dangerous rash called Stevens-Johnson syndrome. Typical adult dose is 300-400 mg per day, usually with 100 mg pills.</p><p><br></p><h3><br></h3><p><br></p><h3><br></h3><p><img src="@@PLUGINFILE@@/Lyrica.jpg" alt="Lyrica" width="400" height="268" class="img-responsive atto_image_button_left"></p><h4><a href="https://www.medicines.org.uk/emc/search?q=pregabalin&amp;offset=1&amp;limit=50&amp;orderBy=company&amp;refreshFilters=true" target="_blank">Pregabalin</a><span>&nbsp;also available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=pregabalin&amp;offset=1&amp;limit=50&amp;orderBy=product&amp;refreshFilters=true" target="_blank">Alzain</a><span>,&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=axalid" target="_blank">Axalid</a><span>,</span><a href="https://www.medicines.org.uk/emc/search?q=pregabalin&amp;offset=1&amp;limit=50&amp;orderBy=newest&amp;refreshFilters=true" target="_blank">&nbsp;Lecaent</a><span>,&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=lyrica" target="_blank">Lyrica</a><span>,&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=pregabalin&amp;offset=1&amp;limit=50&amp;orderBy=product-desc&amp;refreshFilters=true" target="_blank">Rewisca</a></h4><p></p><p>A relative of gabapentin, it may be better, and can be given twice a day. Some believe that it is more effective against seizures than is gabapentin. Pregabalin has no drug interactions, no liver metabolism, no protein binding, and similar side effects to gabapentin. Typical adult dose is 150 - 600 mg bid.&nbsp;</p><p><br></p><p><br></p><p><br></p><p><br></p><p><span style="color: rgb(55, 71, 79); font-family: &quot;Open Sans&quot;; font-size: 1.286rem;"><img src="@@PLUGINFILE@@/Banzel.jpg" alt="Banzel" width="359" height="300" class="img-responsive atto_image_button_left"><a href="https://www.medicines.org.uk/emc/search?q=rufinamide" target="_blank">Rufinamide</a><span>&nbsp;available as&nbsp;</span><a href="https://www.medicines.org.uk/emc/search?q=rufinamide" target="_blank">Inovelon</a><span>, Banzel</span><br></span></p><p>Banzel is approved for add-on treatment of children age 4 and older and adults with&nbsp;<a href="https://www.epilepsy.com/learn/types-epilepsy-syndromes/lennox-gastaut-syndrome-lgs">Lennox Gastaut Syndrome</a>. This syndrome can include seizure types such as atonic (drop) seizures, tonic (stiffening) seizures, myoclonic (brief jerking) seizures, or staring (absence) seizures, as well as partial seizures. Banzel works on sodium channels in brain cells, in a way to make them less excitable. Common side effects include headache, dizziness, fatigue and sleepiness, double vision and tremor (trembling). People who have the “short QT syndrome,” a rare heart rhythm irregularity, should not take Banzel. The drug comes as 200 and 400 mg tablets.</p><p></p><h4><br></h4><h4><br></h4><h4><br></h4><p><br></p><p><span style="font-size: 1rem;"><img src="@@PLUGINFILE@@/Topomax.jpg" alt="Topomax" width="259" height="194" class="img-responsive atto_image_button_left">&nbsp;</span></p><h4><a href="https://www.epilepsysociety.org.uk/topiramate">Topiramate</a>&nbsp;also available as&nbsp;<a href="https://www.medicines.org.uk/emc/search?q=%22Topiramate%22" target="_blank">Topamax</a></h4>A good broad-spectrum AED (i.e., treats all types of seizures). Topiramate has several mechanisms, including blocking the enzyme carbonic anhydrase, which affects the acidity of brain tissue. More acidity (to a point) suppresses seizures. Side effects include thinking and memory problems in about 1/3rd, renal stones in 1-2%, rare cases of glaucoma (increased eye pressure) and weight loss. Typical adult dose is 150-200 mg twice a day.&nbsp;<p></p><h4><br></h4><h4><br></h4><h4><img src="@@PLUGINFILE@@/Depakote.jpg" alt="Depakote" width="270" height="172" class="img-responsive atto_image_button_left"></h4><p></p><h4><a href="https://www.medicines.org.uk/emc/search?q=%22valproic+acid%22" target="_blank">Valproic acid</a>&nbsp;available as<a href="https://bnf.nice.org.uk/drug/valproic-acid.html#indicationsAndDoses" target="_blank">&nbsp;Depakote, Convulex</a>,&nbsp;<a href="https://www.medicines.org.uk/emc/search?q=%22valproic+acid%22" target="_blank">Epilim Chrono</a>,&nbsp;<a href="https://www.medicines.org.uk/emc/search?q=%22valproic+acid%22" target="_blank">Epilim Chronosphere</a></h4>This is the standard broad-spectrum AED (treats all types of seizures) and no other AED is more effective for generalized seizure types. VPA has effects on GABA (at least in very high doses), and a neurotransmitter called NPY to block seizures, and maybe also on calcium channels. VPA has significant side effects: weight gain, tremor, hair loss, GI upset, blood count decreases, hepatic or pancreatic injury, bone weakness over time (osteoporosis), birth defects in up to 10% (folic acid can help to prevent them). Typical adult dose is 250 mg - 500 mg three times a day, but dose can be higher.&nbsp; This is best used on children
(and for bipolar diagnoses with Lithium)<p></p><p><span style="font-size: 1rem;">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</span><br></p><h4><br></h4><p><img src="@@PLUGINFILE@@/Sabril.jpg" alt="Sabril" width="401" height="156" class="img-responsive atto_image_button_left"></p><p></p><h4><a href="https://www.medicines.org.uk/emc/search?q=%22vigabatrin%22" target="_blank">Vigabatrin</a>&nbsp;available as&nbsp;<a href="https://www.medicines.org.uk/emc/search?q=%22vigabatrin%22" target="_blank">Sabril</a></h4><p>At the time of this writing, vigabatrin is approved in the US, but official package insert information has not become available. Vigabatrin is a “designer drug,” made to block metabolism of GABA, the brain’s main inhibitory neurotransmitter. Sabril has been used for over a decade in many countries, and it is effective for partial seizures, with or without secondary generalization. It also may be very effective for infantile spasms, a serious type of seizures in young children. Release in the US was delayed because the drug is toxic to the retina of the eye in up to 30% of people who take it long-term. This toxicity can result in permanent loss of peripheral vision. Regular vision testing is recommended for all people on this drug. A typical regimen begins with 500 mg twice a day, and can increase over a month or two to 1500 mg twice a day.&nbsp;</p><br><br><p></p>