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    Phentermine.. How does it work?
    Ellen1991 posted:
    I've been wondering how specifically phentermine effects weight loss? Does it only decrease the appetite or does it increase metabolism as well? Would a person on phentermine eating 1000 calories a day lose more than a person not taking phentermine eating 1000 calories a day with the same levels or exercise?

    Just curious!

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    Pamela Peeke, MD, MPH, FACP responded:
    Hi and thanks for your posting Ellen. Phentermine is a derivative of amphetamine. It acts very much like all amphetamines including appetite suppression. However, this is short lived. As with all members of the amphetamine family, resistance develops fairly quickly. Then you find yourself needing more and more...and you get the point. The side effects seriously impact upon many people's daily functioning--- difficulty getitng to sleep and/or staying asleep; mood changes including irritability; increased levels of anxiety; feeling edgy and jittery with racing thoughts. It raises your blood pressure and pulse and can produce painful headaches. If people have any medical condition that can be impacted upon like high blood pressure, you have a serious and potentially life threatening problem. Combining with caffeine can be a major problem as well as it's stimulant upon stimulant.

    Next up you don't want to be consuming only 1000 cals under any circumstances. You'll cannibalize your muscle and reduce your metabolic rate. You'll also reduce it by starving yourself. You should be eating no less tha n1200 cals per day.

    If you're consuming only 1000 cals per day, trust me, you won't be doing a whole lot of exercise.

    Bottom line: can the idea of using this medication. Come on, do it the honest and most effective way--- whole foods in appropriate portions plus regular physical activity. That's sustainable. Popping pills will never be.

    Dr Peeke
    Mavrodaphne replied to Pamela Peeke, MD, MPH, FACP's response:
    I am not a doctor. However, I have been on phentermine for nearly six months with great results. I will start by saying I do not have high blood pressure of high cholestrol. My blood work was taken by an endocrinologist and I had all the major targets evaluated; estrogen, insulin, B vitamins, thyroid panel, etc,.

    I have been an avid exerciser and whole food eater my entire life. I put on twenty pounds in spite of my life style in less than eight weeks. Out of the blue, just like that I blew up.

    Thyroid medication for hypothyroidism made me heavier. I gained another ten pounds on that medication, which evidently I need.

    I gave up caffeine as I noticed tea made me feel stimulated. I gave up red wine as it bothered my stomach either due to the thryroid meds or the phentermine?

    I don't get headaches. I sleep all night because I do not drink caffeine. I was advised not to take phentermine after twelve noon or it would keep me awake.

    I do not have heart palpatitations or any of the things you mentioned in your article. I am not starving myself. I eat when I am hungry but I noticed my portions are a lot smaller. I was always energetic but phentermine does speed you up. I can do yard or house work for hours. I have to monitor when I think it's the pill so I don't over work myself.

    I do not have anxiety. On the contrary, my family and friends say I have never been calmer. I can get into my clothes again. I did not lose the two pounds a week as suggested by my MD but lost far more slowly. I have now lost a total of eighteen pounds in six months. I am happy with that.

    Before phentermine, I was advised by general doctors to exercise more and eat less. I did that with absolutely no success. Not at 1,500 calories, 900 calories, no sugar, no carbs. But for some reason; eating all the major food groups including sugar on phentermine works. I think it works because it does reduce your appetite.

    Having said all the above I am about to stop taking phentermine (weaned off it slowly) as my endocrinologist said I can not take beyond a six month period.

    Without the pill I am sure I will put on weight slowly and steadily due to the fact that I will not be artificially stimulated to supress my appetite. It did raise my metabolism levels; I sweat when I exercise alot. I barely perspired running five miles. Now I am drenched. I drink alot of water because I perspire more.

    In closing, I beg to differ with Dr. Peeke. Every single person man or woman will not have identical symptoms or side effects on this diet drug. However, I do agree for those who do not eat right or exercise that you must find a lifestyle plan that works for you.

    If I begin to gain weight again without the phentermine I will find a natural supplement to stave off hunger. More fiber? Plantain leaves? Cellulose?

    I got my life back. I will not reach my weight goal but that's fine. I am happy with what I got from the pill. I highly recommend it for those of you who are medically healthly enough to take it.
    jambajuice replied to Mavrodaphne's response:
    "...It did raise my metabolism levels..."


    In 1959 phentermine first received approval from the FDA as an appetite suppressing drug.

    In 1997 after 24 cases of heart valve disease in Fen-Phen users, fenfluramine and dexfenfluramine were voluntarily taken off the market at the request of the FDA. Studies later proved that nearly 30% of people taking fenfluramine or dexfenfluramine had abnormal valve findings.

    Methamphetamine is a potent central nervous system stimulant that affects neurochemical mechanisms responsible for regulating heart rate, body temperature, blood pressure, appetite, attention, mood and emotional responses

    Because it is similar to amphetamines , it is classified as a controlled substance in many countries.

    Phentermine works on the hypothalamus portion of the brain to release norepinephrine , a neurotransmitter or chemical messenger that signals a fight-or-flight response , reducing hunger.

    The drug may increase blood pressure and heart rate .

    Additionally, phentermine has the potential to cause psychological dependence.

    METHAMPHETAMINE ("Crystal Meth" or "Crank)

    Methamphetamine is the active ingredients in over-the-counter drugs such as Sudafed and Contac.

    Methamphetamine has high potential for abuse and addiction.

    Methamphetamine abuse can lead to prolonged psychiatric disorders, cognitive impairment, as well as increasing the risk of developing parkinson's disease .

    Withdrawal symptoms of methamphetamine primarily consist of fatigue , depression and an increased appetite .

    Methamphetamine use has a high association with depression and suicide as well as serious heart disease.

    To combat addiction, doctors are beginning to use other forms of stimulants such as dextroamphetamine to break the addiction cycle...

    I am glad that you were able to resolve your weight issues.


    With that said, I strongly advise against the use of this narcotic.

    Why you ask?

    "...I am about to stop taking phentermine (weaned off it slowly) as my endocrinologist said I can not take beyond a six month period..."

    Because if it wasn't for your endocrinologist, you'd still be taking it...

    KAREZZ responded:
    It works good but theres side affects that are not good. i recommend not to take it. its best to loose weight by exercising and eating healthy.more health issues come with time of taking this medication.
    TriciaJ518 responded:
    I have been taking Adipex 37.5 mg each morning for the past 2.5 weeks. I have lost over 20 pounds. I recently gained almost 50 lbs after losing my father in May and was stress eating, probably near 3000 calories a day.Then with the stress of being a single mom to a 3 year old the food the caloried added up quickly! I started at 200 lbs and now am down to roughly 180 (at age 24, height 5'5") My appetite certainly decreased and have to sometimes force myself to eat something so my body does not go into starvation mode. But with my appetite decreased I no longer want to eat the potato chips, cookies, fried chicken... I usually eat a yogurt for breakfast and a salad with no fat dressing for dinner. With exercising 2 times a week, chasing my daughter around, and working for 12 hrs on my feet 3 days a week, my weight has certainly dropped significantly. I am very gratedul for this medication. It definitely raises my blood pressure, I am normally at 90/60 and now it runs 120/85 which is normal blood pressure. I do feel energized but that feeling has worn off after the first two weeks leaving only the supressed appetite. I was told that if I stopped taking the medication for a few days and started up again the energy would return. Plus since eating less my stomach has shrunk to accomodate to the average intake of food daily so when I forget or dont take the medication I am still not hungry. The only side effect that I dont like is the slight insomnia- even when I take it at 8 am and dont get into bed until after midnight (i work 11 am-11pm in a hospital ER). But thats a small price to pay to get to a healthy weight quicker to rid myself of worry of serious health conditions. I was adopted so I do not know any family history so therefore I am worried about it all-HTN, diabetes, you name it. This medication certainly works for me and I hope that it works for you as well. Good luck dieters!
    Andie_WebMD_Staff responded:
    Hi Ellen,

    Like Mavrodaphne and others here, I also took Phentermine during my weight loss journey and experienced some success.

    I say "some" because I was already losing weight by curbing my calories and exercising before adding Phentermine to the mix. I had dropped an average of 5-6 lbs a month for 3 months just on my own. When I began taking Phentermine my average became 8-10 lbs per month. I had one good month where I lost 14 lbs, but I was really pushing myself in my exercise routine, and couldn't (or wouldn't) keep it up every month.

    As with any type of amphetamine product, this drug will speed your metabolism up. I seemed to be more alert, quick thinking, and focused on what I was doing. I forgot about eating completely. I also dealt with some extreme dry mouth and began a nervous habit of biting my inside cheek/lip until they were raw. Once I came off the drug, the cheek biting gradually disappeared.

    Just like many other prescriptions, Phentermine can be addicting, so if you have had any other addictive behavior be aware of what you're walking into.

    Whatever choice you make, we are here to support you.

    Before taking ANY type of medication we are always given the side effects and risks to consider. This is no different. Weigh them for yourself, but most importantly, do follow your doctor's recommendations.

    Please keep us posted!!
    Fear less, hope more; Eat less, chew more; Whine less, breathe more; Talk less, say more; Love more, and all good things will be yours. - Irish Proverb
    Ellen1991 replied to Andie_WebMD_Staff's response:
    Hi everyone! I've gotten many mixed replies, all helpful... except that really irrelevant one about meth... o_O

    Since my post I went to a weight clinic and got prescribed phentermine myself. I'm 5'7, and I've been taking phen for a week and three days and have dropped from 141.5 lbs to 135.4 (yay!) I've been eating healthy foods in appropriate portions, and have a very tiny appetite. I'm not exercising all that much though because this is finals week... I'll start running again next week as soon as these terrible exams are finished! The only ill effect I've had thus far is dry mouth, otherwise I'm completely normal except for having a bit more energy. I'm hoping to be at my goal weight of 125-128 soon!

    All though all of your replies where good information to know... I'm still curious about exactly how phen speeds up your metabolism. I read something about it putting your body into fight or flight mode... but I'm still not aware of how exactly that makes you burn more calories when you aren't in the middle of physically fighting of fleeing! I mean... In the past week and a half... I've lost more than I technically should if I had nothing to eat the entire time... My metabolism must be through the roof on this stuff? Either that or it totally dehydrates you... but I've been drinking a TON of water... it's very interesting. It can't only be because of appetite reduction?
    jambajuice replied to Ellen1991's response:

    I apologize for responding to your post...

    I would not have done so if you had specified you were already taking the pills.

    Now that's is clear what you're doing, its perfectly understandable why you would feel offended. Again, I am sorry...

    Good luck and best wishes.
    laura2gemini2 replied to Ellen1991's response:
    This med speeds up metabolism because it causes the body to secrete stress hormones, like adrenaline. That is what causes the fight of flight response. Its the same as if you were to drink an extremely large amount of caffeine. When the body has excess adrenaline, it burns off excess calories and makes the liver secrete sugar. Too much of this can cause nervousness, tics, insomnia, increased BP and heart rate, and loss of apetite. All these side effects are what happens if your body was under a lot of stress naturally as well.

    I am against the use of phentermine, mostly because I know the chemical aspects of what it can do to your body, especially used on the long term. Be very very careful, and have frequent visits with the dr to make sure your heart is OK during this.
    jambajuice replied to laura2gemini2's response:
    Thank you, Laura, for your post.

    "...except that really irrelevant one about meth... o_O..."

    Not relevant? I beg to differ...

    "...The drugs work by stimulating the central nervous system, mimicking the natural effect of adrenalin by increasing the heart rate and suppressing the appetite", Professor Ghodse explains. "Users also feel euphoric and have increased energy levels. However, this also leads to insomnia. Over time, sleep deprivation, coupled with weight loss caused by what basically amounts to starvation, can cause extreme changes in behavior. Users have hallucinations, mood swings, become anxious, paranoid and sometimes violent", he adds.

    And finally, endocrinologists also warn that any weight loss achieved using phentermine is only temporary. "Most people simply put the weight back on once they stop taking the drugs", the Daily Mail quotes Endocrinologist Dr Nicola Bridges, who specialized in the medical treatment of obesity. "These are extremely dangerous in the wrong hands. They have to be prescribed by a doctor who has carefully assessed the risk versus benefit for the patient".

    Coupled with their widespread availability and relatively low costs, weight loss drugs are among the demons of our modern society and cannot be ignored.

    "..When you are abusing diet pills, the danger is typically associated with your cardiac health. It can put you at serious danger for kidney failure, liver toxicity, heart attack and hypertension. These things can be life threatening and it's hard to unring a bell. Once you have damaged a kidney, once you have damaged your heart, it's very difficult for the body to repair those organs.

    And if you've got someone justifying these because they need them for energy or they need them for their appetite, believe me that is the drug talking. That is not a rational human being talking. That should tell you that their judgment is no longer reliable.
    ..." Dr. Phil

    "...That should tell you that their judgment is no longer reliable..."

    I tried...
    An_202182 replied to jambajuice's response:
    While I agree with Dr Phil about the drug speaking when they're just looking for an energy boost, or how certain prescriptions may have an ill effect on organs...I would also ask you, What affect do you think carrying around enough weight to be called obese has on your health, or your organs in particular?

    Every prescription has it's bad side. We could find something wrong with just about anything: prescriptions, OTC medications, certain foods, drinks, vitamins, minerals, etc. The list goes on and on, and it just keeps growing.

    If someone takes phentermine, uses HCG, or any other diet aide to help jump start their weight loss, that is their choice. It sounds like you are saying the ONLY acceptable way to lose weight is the same old "eat less, do more" that we've been hearing forever.

    Phentermine has been approved by the FDA and has been proven helpful. If I were diagnosed with a disease and was told I could either work really hard and take months to improve on my own, or take a prescription that will help me get better in half the time...ummm...No brainer for me even with the effects since the side effects of being obese "outweigh" them.

    Once the weight comes off it's easier to exercise. Once the weight comes off it's easier to maintain the self esteem that makes you want to CONTINUE to eat healthy and exercise. IMO, getting some of the weight off and seeing results sooner is better.
    laura2gemini2 replied to An_202182's response:
    Darvocet was approved by the FDA as a pain killer, and was pulled due to it causing heart problems. Avandia was approved by the FDA, and it was pulled due to it causing heart problems. Bextra was get the idea.

    Sometimes the quick solution isnt the best, as it doesnt work in the long term. Yo-yo weight is worse than slowly losing the weight. Most people are overweight due to a lifestyle they dont want to give up. They've lived this way for years. Taking phentermine wont change that mindset, and once you are off the drug you go back to the same habits and you go back to gaining the weight. That is why people who have bariatric surgery gain the weight back, and they have much more weight lost then if they were to just take phentermine.
    Veenah replied to Pamela Peeke, MD, MPH, FACP's response:
    I have taken phentermine for 2 years. I know, it's not recommended. It helped me lose 70 lbs initially. I have gained back 40 lbs because I am unable to exercise due to an auto accident. The reason I have asked my physician to continue the phentermine is that I go back to my "before phentermine" moody self which is basically acting like I'm PMSing all the time. Every little thing gets on my nerves and I have a very short fuse as well as craving food constantly when I don't take the phentermine, even when I weaned myself off of it slowly. When I take the phentermine I have many of the same effects Mavrodaphne reports - calmness, more effective workouts, less anxiety, more control. I am wondering if anyone else notices that phentermine has a positive effect on their moods and uses it for that effect? By the way, I have never had any succes using anti-depressants (and I've tried quiet a few,) in a way I suppose I'm using phentermine for this use primarily since I can't focus on weight loss right now due to the car accident.
    jambajuice replied to Veenah's response:
    "...I have asked my physician to continue the phentermine is that I go back to my "before phentermine" moody self which is basically acting like I'm PMSing all the time...

    "I have...calmness, more effective workouts, less anxiety, more control. I am wondering if anyone else notices that phentermine has a positive effect on their moods and uses it for that effect?..."

    "...if you've got someone justifying these because they need them...believe me that is the drug talking." Dr. Phil

    Is this a promotion or a warning against its use?

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