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Here is some information for you - courtesy of the good phen fairy.

Drug Information Question of the Week



Posted November 6, 2000



Question:

Is topirimate (Topomax) effective for weight loss, if so how long can the patient stay on it? What is the degree of weight loss expected and what are the side effects?



Background:

Community pharmacist has been receiving many prescriptions for Topomax from a physician. When speaking with the patient, the patient does not have seizure disorder. The patient stated that the doctor prescribed Topamax as weight loss drug.



Answer:

Topiramate has been used as a weight loss agent. A literature search revealed 2 articles that discussed the use of topiramate for weight loss in 3 patients. The patients in these articles had an underlying psychiatric disorder including, bipolar disorder, depression, and chronic schizophrenia as well as being obese. The amount of weight lost in these 3 patients was between 15 and 46 pounds over 2 to 5 months. The dosages used in these patients ranged between 125 mg per day to 300 mg per day. The individuals in these case reports were given topiramate as a mood stabilizer as well as to decrease their weight. After initiation of topiramate an elevated mood, which led to increased motivation to exercise was noted in 2 of the 3 patients. The third patient developed irritability, depression, and anxiety, which led to discontinuation of the medication. No information is available that addressed a safe duration of weight loss therapy with topiramate.



Topiramate is an antiepileptic drug used in combination with other antiepileptics for partial seizures and primary generalized tonic-clonic seizures. It is theorized to exert its effects through blockade of voltage dependent sodium channels, potentiation of GABA transmission, and inhibition of excitatory pathways. The following are the most common side effects associated with topiramate in the first 5 double-blind, placebo-controlled trials of topiramate: dizziness, fatigue, diplopia, nystagmus, somnolence, confusion, abnormal thinking (not psychosis), ataxia, anorexia, impaired concentration, and headache. Anorexia is a dose dependent side effect of the drug, and tends to be higher in women.



Topiramate does produce weight loss in a dose dependent fashion, however the case reports available describe the use of topiramate in individuals who have depressed moods. Literature to support the use of topirimate for obesity without other comorbid conditions is not available.



Jon Ellison, PharmD Student

Univeristy of Florida College of Pharmacy



References:



1. AHFS Drug Information 2000.



2. Dursun, S., et al. Clozapine Weight Gain, Plus Topiramate Weight Loss. The Canadian Journal of Psychiatry, March 2000; 45 (2): 198.



3. Gordon, A., et al. Mood Stabilization and Weight Loss with Topiramate. The American Journal of Psychiatry June 1999; 156 (6): 968-9.



4. Perruca, E. A Pharmacological and Clinical Review on Topiramate, a New Antiepileptic Drug. Pharmacological Research 1997; 35: 241-56.





Does Topiramate Cause Weight Loss?

Source: Acurian, Inc.

by: Andrea F. Luisi, PharmD, BCPS



12/18/2001



Biography: Andrea F. Luisi 's clinical practice and primary research interest is in geriatric pharmacotherapy. Currently, she is involved with several multidisciplinary research groups at the University of Rhode Island. She is an active investigator and author and currently serves as reviewer for Annals of Pharmacotherapy.



Commentary: Topiramate (Topamax(R)) is an antiepileptic agent that is used for the treatment of seizures or epilepsy. Topiramate was approved by the FDA as adjunctive therapy (meaning used with another agent) for adults and children 2-16 years of age with partial onset seizures, or primary generalized tonic-clonic seizures, and for those over the age of 2 years with seizures associated with Lennox-Gastaut syndrome. Results from a number of small studies and case reports also suggest that topiramate may be beneficial in the treatment of mood disorders, such as bipolar disorder.



Weight loss has been reported with the use of topiramate. In human studies of topiramate for the treatment of epilepsy, patients have reported weight loss. Animal studies, mostly in rats, have also shown that topiramate tends to cause weight loss and can decrease fat deposition or storage. These effects may be a result of topiramate causing a decrease in food intake or an increase in energy expenditure/output.



According to the manufacturer, up to 13 percent of subjects in clinical studies taking 600-1000 mg per day of topiramate experienced weight loss, as compared to 9 percent of those taking 200-400 mg per day and 3 percent of those taking placebo (a sugar pill). Cases published in the literature have reported weight loss of up to 20 percent of baseline weight with topiramate. In most of these cases, topiramate was being used for the treatment of a mood disorder.



There have also been published case reports of topiramate's beneficial effect in people with binge-eating disorder (also known as bulimia). In these reports, topiramate was associated with a weight decrease as well as a decrease in the frequency of binge-eating behavior.



Please be sure to check with your healthcare professional before making any changes in your drug treatments.



Would you recommend topiramate as an agent for weight loss?



Weight loss has not been a primary outcome measure in clinical studies of topiramate, meaning that topiramate has not been specifically studied to test how it affects weight. We also do not know if the weight loss will continue, if weight will be maintained, or if weight will increase with long-term use of topiramate, or what will happen if topiramate is stopped. Therefore, at this time there is not enough data to support the use of topiramate for weight loss. If a patient has another reason to be taking topiramate therapy, such as epilepsy or a mood disorder, and also happens to be overweight or obese, they could ask their physician if topiramate is an option for them.



What are some of the other side effects of topiramate?



Topiramate is also associated with fatigue, dizziness, nervousness, difficulty with concentration/attention, confusion, anorexia (loss of appetite), and anxiety.





Johnson & Johnson have announced that obese patients lost over 11 percent of their body weight one year after being treated with the company's anti-epilepsy drug Topamax.



The firm is encouraged to continue developing the medicine as a weight-loss medicine.



Topamax is currently approved only for treatment of epilepsy, but the New Brunswick, N.J.-based firm is also conducting studies to test its efficacy for a variety of other conditions -- including obesity, neuropathic pain in diabetics, to prevent migraine headaches and to treat bipolar mania.



Joe Scodari, a senior J&J research executive, told analysts at a meeting in La Jolla, Calif., that one of the most exciting new potential uses of Topamax is for obesity.



He said an 11 percent to 12 percent weight loss was seen in obese patients that took Topamax in an earlier clinical trial for one year as a treatment for epilepsy. "I don't know of any other product (drug) doing that," he said, referring to the magnitude of the weight loss. Epileptics who were not obese also lost weight in the trial, but less than obese patients, he added.



The company said the potential sales of Topamax for obesity were "huge," but declined to speculate when clinical trials for the condition or for the other new indications might be completed.





MIAMI -- Anyone on migraine medications knows the side effects of these drugs often includes weight gain -- but the migraine and seizure fighter Topamax is working in just the opposite way -- helping some people accomplish what diets can't.



Diana Evans has battled migraines for 16 years. Several months ago her doctor neurologist Randolf Evans put her on the migraine medication Topamax, and Diana says, "The migraines just stopped." But she still had her other battle -- that of the bulge. "I've tried everything -- weight loss drugs -- liquid diets -- exercise." To her surprise -- Topamax not only helped shed the migraines but she's in the 20 percent of patients who have also seen packed on pounds vanish.



Evans lost close to 20 pounds and says she didn't have to do anything. "You're hungry but you just don't crave the foods that you used to crave." Dr. Evans says Topamax makes carbonated drinks taste bad for some people, which may be one reason why they lose weight.



Other theories include that the drug somehow suppresses appetite. "There's also a possibility that the drug could work in the hypothalamus and they may have an increased metabolism as lose weight for that reason." Dr. Evans says. "I've had a number of patients who have lost 20-and-30 pounds. The most one of my patients have lost is 70 pounds. I've heard reports of patients losing up to 120 pounds on the medication."



The makers of Topamax are conducting studies to see just how effective this is as a weight loss treatment.



Doctors agree Topamax is safe, but it does have some possible side effects:



Nausea

Fatigue

Numbness or tingling in extremities

Altered effectiveness of birth control pills



In rare cases, Topamax may also cause early symptoms of glaucoma.



As for Diana Evans, she recommends anyone not having success with their migraine medication to talk to their doctor about Topamax. You may even be one of the lucky ones like Diana who loses weight on it.



Topamax is a prescription medication so make sure to check with your doctor to find out if it's right for you.





Topiramate wards off weight gain -



The epilepsy drug topiramate (Topamax) may help patients combat weight gain associated with selective serotonin reuptake inhibitors (SSRIs), say researchers at McMaster University in Hamilton, Ont.



The team studied 15 anxiety disorder patients who had gained an average of about 13 kg while taking an SSRI. They added topiramate (mean dose 135 mg) to treatment for about 10 weeks. Subjects lost an average 4 kg.



Dr. Michael Van Ameringen, an associate professor of psychiatry at McMaster, said topiramate could be curtailing future weight gain, as well as resulting in weight loss. He said for most patients the weight loss appears to plateau, but one woman who continued on topiramate lost 27 kg, having gained 36 kg while taking fluoxetine (Prozac).



Their results suggest a course of topiramate may be worth trying, particularly since switching the patient's SSRI is risky, he said. "If you change to another SSRI, you don't know if they're going to respond."