weight loss lesson

Since it was first approved by the FDA in 1959, phentermine has helped millions of people lose weight, and for this reason it’s still the most widely prescribed weight loss medication in the US. However, if you’re unsure about how phentermine works, we’re here to explain everything you need to know to feel fully informed about how phentermine helps you lose weight.

How Does Phentermine Work?

Contrary to what some people believe, phentermine is not a miracle pill which can help you lose weight without exercise or watching what you eat. Phentermine doesn’t promise to magically burn fat or melt away the pounds, it’s YOU who has to do the hard work. However, phentermine makes things easier for you by reducing hunger and giving you energy. This means that you’re better able to establish healthy eating habits and incorporate more activity into your lifestyle. Here we explain in more detail how phentermine helps you lose weight by suppressing appetite and boosting your energy levels:

1. Phentermine Suppresses Appetite

Phentermine causes the brain to stimulate the adrenal glands to release neurotransmitters which signal a fight-or-flight response, similar to the reaction of our bodies when we are faced with dangerous or exhilarating situations. By releasing the neurotransmitters norepinephrine, serotonin and dopamine, phentermine helps your body to create a satiating effect, increasing feelings of fullness, minimizing hunger, and reducing cravings. The appetite-suppressing effects of phentermine can vary but most people will experience less hunger than without phentermine, and will also notice that phentermine helps them to feel full much quicker than they normally would.

How Does This Help Me Lose Weight?

For many people, establishing more control over appetite and cravings holds the key to weight loss. This is because those who have tried and failed to lose weight by diet and exercise alone often struggle with problems related to appetite cues, satiety regulation and cravings related to food addictions and emotional issues. While it is not known if this problem originates as a result of genes, psychological issues, or is due to many years of eating badly, by manipulating neurotransmitters to control satiety cues, phentermine helps obese patients regain control of their eating for what may be the first time ever.

With a reduced appetite, you should still experience feelings of hunger, but one that is satisfied with fewer calories than you would have typically needed before taking phentermine. Most doctors and weight loss experts agree that a minimum of 1,200 calories should be consumed each day, but that this daily allowance could be set higher, depending on the patient’s start weight and loss required to reach a healthy BMI and body fat content. It is then up to you, with help and advice from your phentermine doctor, to make the right choices when it comes to establishing a healthier diet. This new way of eating should comprise of a variety of nutritious foods which also work to keep hunger at bay, such as foods high in fiber, protein and healthy fats. Furthermore, by reducing your appetite, phentermine helps you achieve the focus necessary to change your eating habits without distraction from misplaced hunger cues and cravings. This means that you can eat the right foods in order to provide your body with the essential nutrients and vitamins required for good health and successful weight loss.

how does phentermine help me lose weight

2. Phentermine Boosts Energy Levels

The fight-or-flight response that phentermine simulates also causes the release of adrenaline, improving your chances to deal with a physically demanding situation. Through the release of adrenaline, phentermine stimulates various bodily functions to increase glucose levels and fatty acids in the body, breaking down food more efficiently to increase energy production within the body’s cells. These changes allow more blood to get to the muscles and more oxygen to fill the lungs, so that you’re ready to use this energy to either flee from danger or defend yourself.

How Does This Help Me Lose Weight?

Well, in the case of phentermine, rather than helping you to stay and fight or run from danger, this extra energy means that your body wants to expel this rush of adrenaline and energy by increasing activity levels and participating in physical exercise. As phentermine is structurally similar to amphetamine, in addition to the boost of energy it provides, phentermine helps you to remain focused on your weight loss goals and avoid snacking by amplifying feelings of concentration and alertness. Accordingly, it is advised that phentermine is taken early in the day so as to avoid insomnia at night because of the increased energy and feelings of alertness it provides. When first taking phentermine, many patients report feeling ‘wired’ or describe a ‘buzz’ feeling that gives them the boost they need to focus on their weight loss goals and incorporate more activity into their day. However, these feelings often lessen after the first few days once the body becomes more accustomed to the effects. Lastly, the extra energy from phentermine helps you avoid common afternoon cravings that result from the energy slump many of us experience a few hours after lunch.

How Much Weight Can I Lose With Phentermine?

It is very difficult to say how much weight you will lose with phentermine as individual differences between patients such as age, start weight, activity level, and diet mean that weight loss results can vary a lot. Depending on your lifestyle prior to taking phentermine and the changes you make once you start, such as if you greatly increase your water intake, it is often possible to lose several pounds in the first week as your body sheds water weight. After this first week or two, your weight loss results will slow down, which is to be expected as the recommended weekly rate of weight loss is one to two pounds; this rate ensures that your body is losing fat and not precious muscle, which your body needs to retain in order to assist with fat burning. A rate of around 2lbs per week is also achievable in the long term once your phentermine prescription has finished.

It is important to remember that phentermine is intended for the short-term management of obesity, and is typically prescribed for 12 weeks at a time. Phentermine is usually only prescribed for short periods due to the effects it can have on the body, including a potential to put pressure on the heart and cause a variety of side effects alongside the desired effects of appetite suppression and extra energy. The side effects include dry mouth, mood swings, and insomnia – you can find advice related to how to combat the side effects of phentermine here. The majority of phentermine side effects should decrease over time, but if you experience any concerning or unpleasant side effects then you should speak to your doctor immediately.

Phentermine is also not something that can be taken long term as it becomes less effective as your body gets used to the medication. One way to ensure that phentermine continues to work for you, is to combine your phentermine prescription with Phen Caps, the phentermine alternative recommended by us here at phentermine.com. Phen Caps can help enhance the effects of phentermine while you are taking it, or as you come to the end of your prescription. Like phentermine, Phen Caps help you to lose weight at a steady rate by suppressing appetite and boosting energy levels, so you will be able to continue with your weight loss journey even after your phentermine prescription has finished. Similarly, if your doctor decides that phentermine isn’t right for you, then Phen Caps are the ideal non-prescription alternative to phentermine.


Now you know EXACTLY how phentermine helps you lose weight, we hope you feel fully informed about how it works. However, if you have any questions then please feel free to comment below!


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8 Responses

  1. I work at night 12 hr shifts 7pm-7am. what is the best time for me to take phentermine?

    • Hi Sandra,
      This article: http://www.phentermine.com/blog/manage-lifestyle-phentermine/ has information about how to manage different lifestyles with phentermine. It states: “For some people, it may be a case of having to wake up later or at different times due to working nights or varied shift patterns. For those of you who work nights, you should take your phentermine when it’s your ‘morning’. Explain your personal timetable to your doctor and this will help you both come to an arrangement which is likely to include you taking your phentermine when you wake up in the afternoon and then eating either a snack or your dinner around an hour later. Taking your phentermine in the morning before you sleep is doubly counterproductive, as it is likely to affect your ability to sleep during the day, and then the energy boosting effects and appetite suppression will be reduced when you need them most during the early hours of the next morning. It can be a little more complicated for those of you working different shift patterns from week to week or even day to day, but essentially, the same advice applies; the optimum time to take your phentermine will be when you first wake up, whatever time that may be, so as to make the most of the extra energy and appetite suppression during your particular waking hours.”
      Hope that helps!
      Sally, phentermine.com

  2. I just wanted to share my short experience. Started this on 10/8/16 at 181.4. Now *10/11/16 down to 176 however after today I will be stopping. I work in an ER and started the morning out with palpitations hr in 130s. Stuck it out they subsided but left a dull chest pain continued on through the day…. talked to someone who told me she went into cardiac arrest on this pill… a light clicked in my head… did am ekg was abnormal with inverted t waves… I’m a healthy 27 yr old with just some anxiety and last ekg in Jan was normal. Labs came back all good except potassium was a little low. So now I need to follow up with a cardiologist bc it’s still not sure if it was my potassium or the drug. So with 2 little girls that need me I will not be taking anymore as of tomorrow. (thankfully I was only on it 3 days) the weight coming off was nice and made me happy for once… now I’m just depressed and sluggish but I’m trying to take today as a sign that it’s just not for me and hoping I wake up tomorrow morning.

  3. Incorporate some cardiovascular exercise into your life you will feel better and continue to lose weight…just saying

  4. Does this pill have a tendency to make you lose your hair?

  5. Is it safe to exercise while taking this pill?

    • Hi Marissa,
      Yes definitely, exercise is highly recommended for more effective weight loss on phentermine and weight maintenance once you stop the medication. If you have heart problems or any other medical conditions that you’re worried about then you should speak to your doctor who will be able to recommend the best types of exercise for you specifically.
      Sally, phentermine.com

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