Well this might be not what you want to hear, but because I care I'm going to say it anyway, and this won't be sugar coated, but believe me, this response is in your best interests not mine
Hydroxycut to my knowledge also caused issued due ot things lik Undiagnosed Heart and Thyroid issues, not necessarily through misuse.
The FDA could use this as a nail in the coffin for Metabolic Enhancers, which includes Appetite suppressants and Thermogenic serums, but they won't, it's the same for anyone with the authority to do something like that but doesn't.
Classic example. A dangerous stretch of road in Britain, caused 5 serious accidents and 2 deaths in about 6 years, before anyones concerns were finally attended to.
People often who could do something in such situations, dismiss peoples concerns, until hindsight plays its part. too little too late for some.
The fact you haven't had a problem, doesn't mean you couldn't. If you have caused any possible damage to the Thyroid, you could with wear and tear and aging, end up with problems or possibly even a Thyroid disease.
Any such products even Alli, Hoodia supplements, Thermoslim, Adios etc etc, are at best a useless scam, at worst a danger to life.
If they worked, fat people could take them, and either get slower weight gain, no weight gain or weight loss, depending on the severity of their lifestyles and body composition.
After all, how many people take chemical or herbal medicines, and get told you need a calorie controlled diet and exercise programme, before your meds work? You don't. Sure some contraindications, like if you're on Heart meds, avoid Caffeine, possibly things like Grapefruit and the juices, certain supplements, alcohol, etc etc, but a Doctor couldn't say, don't eat deep fried food or your Warfarin or Ramipril etc etc, wouldn't do jack for you, because that's crap.
At best suggest you stop eating it, but I personally don't think any medication would completely fail, if someone continued to eat certain unhealthy things, or even continued with some vices. A medication might fail if it wasn't the best choice for a certain person
The warning with Hydroxycut was there, the moment any Metabolic Enhancers first hit the shelves. It was never about and has never been about Hydroxycut. They were just the first ones to open a gaping wound in the supplement industry, Frankly it could have been anyone, but it wasn't.
The best thing you can do, before you put your health at any possible further risk, is just totally forget those products. If you love yourself, don't pay for things that could physically hurt you. You deserve better for your money that a slow road to ill health.