Reply To: TOPAMAX, anyone taking this med?

October 16, 2008 at 4:55 pm

I thought your post was titled “Anyone taking TAMPAX?” I think I need my eyes checked, LOL.

I Googled topamax & Wiki had a good explanation. Here is the link: [url][/url]

And here is the text:
Topiramate (brand name Topamax) is an anticonvulsant drug produced by Ortho-McNeil Neurologics and Noramco, Inc., both being divisions of Johnson & Johnson. Generic versions are available in Canada and were FDA approved in September 2006 . Mylan Pharmaceuticals was recently granted final approval for generic topiramate 25, 100, and 200 mg tablets and sprinkle capsules by the FDA for sale in the US. 50 mg tablets were granted tentative approval. It was discovered in 1979 by Drs. Bruce E. Maryanoff and Joseph F. Gardocki during their research work in McNeil Pharmaceutical.

This drug is used to treat epilepsy in both children and adults. In children it is also indicated for treatment of Lennox-Gastaut syndrome (a disorder that causes seizures and developmental delay). It is also Food and Drug Administration (FDA) approved for, and now most frequently prescribed for, the prevention of migraines. It has been used by psychiatrists to treat bipolar disorder, although it is not FDA approved for this purpose. This drug has been investigated for use in treatment of obesity, especially to aid in the reduction of binge eating, and also as a possible treatment for alcoholism. However, these uses are not actively promoted by the manufacturer, and like its use for bipolar disorder, are off-label uses.

The drug is also used in clinical trials to treat Post Traumatic Stress Disorder. A pilot study suggests that Topiramate is possibly effective against infantile spasms. A study by Harvard recommends topiramate as an effective treatment in the prevention of Periventricular leukomalacia in preterm infants after an hypoxic-ischemic injury. In May 2006 the U.S. National Institutes of Health web site listed several studies sponsored by Ortho-McNeil which propose to examine the use of topiramate on migraine, cluster, and severe headaches within various demographics. Other off-label and investigational uses of topiramate include: treatment of bulimia nervosa, obsessive-compulsive disorder, treatment of alcoholism, smoking cessation, Pseudotumor Cerebri, and treatment of neuropathic pain.

Chemically, topiramate is a sulfamate-substituted monosaccharide, related to fructose, a rather unusual chemical structure for an anticonvulsant.

Topiramate is quickly absorbed after oral use. Most of the drug (70%) is excreted in the urine as unchanged drug. The remainder is extensively metabolized by hydroxylation, hydrolysis, and glucuronidation. Six metabolites have been identified in humans, none of which constitutes more than 5% of an administered dose.

Topiramate enhances GABA-activated chloride channels. In addition, topiramate inhibits excitatory neurotransmission, through actions on kainate and AMPA receptors. There is evidence that topiramate has a specific effect on GluR5 kainate receptors. It is also an inhibitor of carbonic anhydrase, particularly subtypes II and IV, but this action is weak and unlikely to be related to its anticonvulsant actions, but may account for the bad taste and the development of renal stones seen during treatment. Its possible effect as a mood stabilizer seems to occur before anticonvulsant qualities at lower dosages. Topiramate inhibits maximal electroshock and pentylenetetrazol-induced seizures as well as partial and secondarily generalized tonic-clonic seizures in the kindling model, findings predictive of a broad spectrum of activities clinically.

Its action on mitochondrial permeability transition pores has been proposed as a mechanism.

It also is a sodium channel blocker.

A GlaxoSmithKline-sponsored Phase IV (post-marketing) study suggested that cognitive side effects may be more common with topiramate than with lamotrigine.[24] In studies of healthy volunteers, comparing the two medications, therapeutic doses of topiramate for bipolar disorder produced greater cognitive deficits than lamotrigine, including short term memory loss and word-finding difficulty. This effect has led to the occasional use of the name “dopamax” by some dissatisfied customers. A flat affect was reported in > 75% patients (n=60).