Duromine vs. Phentermine/Topiramate ER In terms of contrasting and comparing Duromine and Phentermine/Topiramate ER we are going to find out if the ingredient alone can effectively compete with the combination. Under the latter the same component, Phentermine, enhanced with an additional one, Topiramate, is being implied. Up to now Phentermine/Topiramate ER (known as Qsymia) has been considered to be the only successful combination the number one weight loss drug could allow without losing its remarkable qualities and producing great results rather than causing severe side effects. A couple of previous ones, Fen-Phen and Dexfen-Phen, have turned out to be a failure rather than an announced overnight sensation. So let’s proceed. 25 vs. 4 The aforementioned figures show how long both drugs have been around. For the moment prescription medication Duromine has been available for sale upon its approval in 1991 for nearly 25 years. That is quite a long period of time during which the drug has managed to establish itself as a working, well-tolerated weight loss med. So, even if it is going to leave the market one day, suitable replacement for it will be found. Unlike Duromine, Phentermine/Topiramate ER got its approval in 2012. So, now it cannot boast of a long-term and successful treatment history, which is certainly a con, as it is still under some sort of trial. As a point of reference, an approved market life of Fen-Phen cocktail is 5 years only; owing to Mayo findings and numerous additional reports of heart diseases received from patients it was withdrawn from the market. No hints, no parallels, but Phentermine/Topiramate ER still has to deserve the right to be called a tried and true weight loss drug just like Duromine. Formula and Dosage Form To clearly underline a major difference between Duromine and Phentermine/Topiramate ER let’s break down the components investigated. Phentermine is a centrally acting appetite suppressant that in addition to this major hunger subduing property also increases the metabolism. It does that by releasing a number of chemicals both within the brain and outside it. Topiramate is an antiepileptic agent commonly associated with weight loss, which is known to be its side effect. The mechanism with the help of which this drug produces its weight loss effects is still unknown. Duromine is based on Phentermine and its properties only. In the formula of Phentermine/Topiramate ER the second ingredient was added to enhance weight loss properties of the drug seeming to be in wide use for ages. This should have pushed Phentermine/Topiramate ER far ahead of Duromine but for one feature. That’s where comes the difference that matters a lot. Each and every Duromine capsule is manufactured as an ion-exchange resin complex. The duration of the anorexigenic effect produced after the capsule’s application is about 25 hours. Owing to this resin complex, Phentermine is released gradually, within 10-14 hours. This means the drug works all this time. There are more than 30 Phentermine-based drugs, and only three of them apply a time release technology of this kind. Dosage form of Phentermine/Topiramate ER is a hard gelatin capsule that contains immediate-release Phentermine beads and extended-release Topiramate ones. If compared with Duromine’s resin complex, this dosage form allows fewer variants for dose adjustments, which may be crucial in some cases, as weight related comorbidities differ.