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An FDA approved diet pill for obese patients.

QUICK FACTS Start the Diet Now Advertisement
  • Established: 1959 FDA approval; available in the 1970s; removed from the market voluntarily in 1997 but still available
  • Founder: Originally sold by King Pharmaceuticals; currently made by several companies
  • Accessibility: Prescription only
  • Diet Type: Appetite suppressant to be taken short-term
  • Gender: Male and female

Phentermine is a short-term prescription appetite suppressant that works by stimulating the hypothalamus gland and affecting neurotransmitters in order to decrease your appetite. The hypothalamus gland is the portion of the brain that controls many functions, including your appetite. Combined with proper nutrition and exercise, you can see weight loss results

  • Phentermine is given under doctor supervision
  • Formulated specifically for the obese
  • Documented success stories
  • Suppresses appetite
  • Short term help to lead you to eat healthy and exercise
  • FDA approved
  • Generic version available which is cheaper than name brand

  • Phentermine has the potential of many serious side effects, including: chest pain, fainting, swelling of feet or lower legs, trouble in breathing, among others
  • Currently available by prescription only
  • Not a long term solution
  • Side effects of dry mouth, blurred vision, constipation
  • Phentermine Hydrochloride (HCL), along with a host of non-active ingredients.

Your doctor will decide on your dosage and instructions for taking Phentermine when giving you the prescription. The average dose is 30mg of Phentermine per day, but some patients are prescribed to start off with 15mg per day.


It is recommended that you incorporate diet and exercise into your plan when taking Phentermine. Phentermine is a drug to be taken only on a short-term basis. After six to 12 weeks, you are advised to discontinue taking Phentermine, and continue with your diet and exercise plan to reach your weight loss goals. Phentermine is only intended to help the obese kick start their weight loss plan while they become used to following a low calorie diet and exercise plan.


When you're talking about a prescription weight loss drug, you have a product reserved for people with the most dire of needs. So, obviously this is not for everyone. If you have health problems related to obesity, and you fell you need help in getting some of your weight off, consult your doctor about Phentermine.

Common Misspellings

fentermin, fentermine, phentramine, phenterthin

Related Diets: Adipex-P, Alli, Fedramine, Phenterthin, Phentramine

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(Page 5 of 13, 248 total comments)


I started taking this amazing diet pill in September of 2010. I throughout the whole time i was on it i was only taking a half of a pill except one month i took a whole pill. I am very overweight. When i started in september i weighed in at 280. In January i was down to 226. My goal weight is 160-180 for some that is still overweight but I am very big built and have been BIG all my life so i dont want to look sick.

During my time on the pill I didnt work-out much i didnt have time but i could only imagine how much i would have lost if i had been working out. I recoment this pill to EVERYONE I talk to about weight loss.

I have been off the pill since the middle of January and by geez i can FOR SURE feel the difference. I have also started gaining weight back prolly 20 pounds :(

The only downside to this pill is if your body isnt fully adjusted when you get off the pil the weight will come right back on QUICK!! Most people when they get off it gain back more than they had lost in the first place.

Good luck to those looking to try the pill and everyone wish me luck getting to my weight goal!! I will update everyone as i get my results from my doctor.

posted Apr 20th, 2011 5:22 pm

Kenia Felix

Ok.... SO after much thought I am starting the prescription tomorrow. My weight now is 170 lbs my mini-goal weight is 145. My ultimate weight loss goal is 130. Wish me Luck!!!

posted Apr 15th, 2011 3:49 pm


I started gaining weight when I was 19 years old after trying several different medications for PCOS. My weight sky-rocketed and i've struggled ever since. I heard about Phentermine through a friend and decided to ask my doctor.
I started Phentermine in December 2010 weighing 251 pounds, i'm 5'7 and 24 years old. It is now April 2011 and my weight is at 217. I don't work out regularly but am planning to start. My blood pressure has dropped and I feel amazing. My goal is to get to 180, I know that's still high (to society) but i'm built like a line backer anyways lol.

The side affects I have are dry mouth, blurry vision and restlessness. I think this drug is a gift, I highly recommend it to anyone. I take it first thing in the morning so the jitters where off before bed time. If anyone needs any help or answers, please ask. Good luck everyone!

posted Apr 15th, 2011 8:15 am


I've lost 17 lbs in a month taking phentermine/B-12 weekly shots. I haven't experienced any side effects, other than dry mouth. It helps cut down the cravings for me and I have make myself eat because i'm not hungry. It's not a miracle, don't get me wrong. I have been eating healthy, counting calories and exercising lightly.

posted Apr 4th, 2011 7:30 pm


I'm a 5'9" female and started my weight loss plan at 255lbs (yikes). My blood pressure was way too high (155/90) and i'm 41 years old. Between December 15th through March 8th I lost 13 pounds by eating right and light exercise. On March 8th I started the B12/phentermine plan with my Doctor and as of today 4-4 I'm down to 225(still too high, but on the right track). So, in the past month I have lost 17 pounds for a grand total of 30. And, my blood pressure has been 120/90 the past few weeks. I firmly believe the weight loss shot and phentermine have helped. However, it is not a miracle. I have been very careful about what I eat and have continued with light exercise. I have had no negative side effects from the phentermine pill, other than "dry mouth" and the shot gives me energy. I say to those that are considering this option, try it, it works but you have to watch what you eat too and make lifestyle changes. The pill seems to make it easier. I know longer have nagging thoughts of pizza and chinese food! I have even started taking it every other day because I was not getting enough calories in the day, simply because i was not hungry. Also, if you are calorie counting, the website is awesome! it makes it so easy to keep track of calories and other nutritional information. it even has tons of recipes! i love it. Good luck to all, losing weight is HARD.

posted Apr 4th, 2011 6:57 pm


I started taking Phentermine on 3/22/11 it is now April first and I am down 12 pounds in not even 2 weeks! I am very satisfied with this product so far! I just makes me not hungry. I used to crave chocolate, candy anything sweet pretty much all the time and I havent even wanted anything sweet since I started taking this medication. I literally do not feel the need to eat so I drink 2 slim fasts a day and have a small meal for dinner, so far I have not done any exercise since I have started taking this medicine and I am still losing weight! I am hoping to drop about 60 more pounds and be smaller than I have ever been!

posted Apr 1st, 2011 1:45 pm


I am fixing to start taking phentermine on 4/1/2011...I currently weigh 265 and mhy goal is 180....I know with hard work and willpower I can do this. Any advise from anyone on what to eat and what to stay away from would be greatly appreciated....I am a snacker....

posted Mar 30th, 2011 8:35 pm


My doc gave me Phentermine in Sept 09. My starting weight was 186lbs. Within the first month, I lost around 15lbs without working out. It completely took away my appetite. I had to force myself to eat. When I did eat, I ate very small portions. It gave me tons of energy...which did cause problems with my sleep.I also had dry mouth which did help me drink tons of water. After the first month, the side effects did not bother me too much. By Dec 09, I dropped to 145lbs and stopped Phentermine. I felt more confident. I started to work out and tone up. But no matter how much I dieted or worked out, I could not get a flat tummy. In May 2010, I decided to have a tummy tuck. Went back to my doc to get more Phentermine to take during my tummy tuck recovery since I would not be able to exercise. Exactly six weeks after surgery, I was down to 139lbs. I stopped Phentermine. I gained a little over 10lbs during the six months after that. It is now Mar 2011...I gained another 15lbs due to some medication I started in January. So total, I'm up 25lbs. I am now in the "overweight" range for my height. My doc gave me a script for 2 more months of Phentermine even though I am not "obese" because he figures why wait till someone gets to that point. He also knows the struggle I went through with the surgery and doesn't want the weight gain to affect my results. I restarted the Phentermine today. I am so thankful for this medication. It has really helped me. I don't know why it isn't prescribed more often.

posted Mar 30th, 2011 5:50 pm


I have been using Phentermine for a week now and have lost 5 lbs. It's ok except it's not as strong as it was the first couple of days. Still supresses my appetite just doesn't control cravings much anymore. Also, I am doing weight watchers and excercising so I can't really say for sure if the weight loss is from the phen or my diet and exercise.

posted Mar 30th, 2011 2:38 pm


Hello again

Just an update on my progress...I started working out yesterday-using the treadmill and elliptical. I took my dosage about 1030 and decided to go work out around 1130. I started walking on the treadmill with 3.7 speed, 1.5 incline. Now I'm not a stranger to the gym; however, in the past I didn't push myself. My daily rountine was pretty much the same but every once in a while I would get hyper and jog at 5.5-6.0 speed and 3 incline. Needless to say, yesterday I gave it a little push, with my boost from the Phentermine, 4.5-5 speed and 1.5 incline, WELL my HR had reached and alarming 186. OMG when I saw that I was terrified because it was extremely usual for me but felt I could push twice as much even from that point. I said all that to say...guys and gals...IF you incorporate a work out with your reigmen Phentermine...PLEASE monitor your HR. I'm not a doctor but I think this is very important.

Until next time...

posted Mar 25th, 2011 7:04 am


Hi Frankie...I think Phentermine is as good as its gets but thats just my opinion. I have tried many so called "diets" and this is the ONLY thing that worked for me...especially the same day and continously. Also, you have four months so with a low cal diet and light work out, you should do well. Stick to your plan and good luck. And btw congratulations!

posted Mar 25th, 2011 6:48 am


I two phen for two weeks lost 7 lbs but I had bad side affects like chest pain....

posted Mar 25th, 2011 12:25 am


i started phentermine to day 5'1 and 194 pounds i getting married in 4 months and if anyone can give me ideas to lose weight a lil faster plz help me

posted Mar 24th, 2011 12:28 am


Countdown to weigh loss!I am 41 years old, 5'3 and 143 pounds. I am starting phentermine 15 mg on 3-19-11. I am a healthy eater and exercise regularly. My weight just wont come off! My doctor, whom I love, has given me a one month RX. I look forward to posting my results in one week!

posted Mar 18th, 2011 12:58 pm


I started Phentermine 37.5 yesterday. Although I take 1/2 capsule, I think this thing is working. I can't believe it. I don't feel hungry and no jitters. I have; however, experienced massive chills and a little light-headed. I haven't started working out because I wanted to see how my body react to the pill. Its only been two days so I will probably feel more comfortable pushing myself this weekend.

I think this is a wonder pill...finally something that works almost instantly. I will keep you posted on my progress.

posted Mar 16th, 2011 1:15 pm


Just started Phentermine 37.5 this morning. 5'6" 196 pounds. Wish me luck!

posted Mar 8th, 2011 7:27 pm

Mrs. MI

Ive been taking phentermine 15 mg for about a month and a week! Best decision ever! I've lost 25 lbs so far! Im Hoping to lose abt 35 more and it hasnt been easy but I am definitely committed! DO IT!

posted Feb 24th, 2011 12:56 pm


i am 5'4 and have always been a little chunky. My weight was getting out of control, so I went to a weight loss clinc, that my mother in law and sister in law go to, on thursday 02/17/2011 and I weighted 208. That is the most I have ever weighed. I got a lipotropic/b12 shot that day and started the phentermine 37.5 pill the next day. It has only been 5 days since the doctor visit. I haven't weighed myself yet, but I think I have lost some weight. I only drink water now. I don't eat snacks or sugar anymore. I don't excerise at this time, but I plan on starting that soon. I have read a lot of reviews and I hope I am lucky enough to lose a lot of weight.
The first 2 days I only took half a pill (like the doctor told me) and I had a terrible head for those 2 days. I ususally gets headaches anyways, so it didn't bother me. I haven't had a headache since then. It look me a little longer to fall asleep at first, I couldn't turn my brain off and stop thinking for a while, but that has also subsided. My mouth is dry so I am constantly drinking water (which is good). I do not feel hungry at all anymore, I have to force myself to eat. The only other thing I noticed is that I use to remember my dreams every night in very good detail and since I've started these pills, I can't remember any dreams I have.
The doctor office I went to gave me 3 more shots ( to take home and take every week of the lipotropic/b12 ). I have to go back after a month to get another prescribtion for the pills and the shots to take home. I'm hoping I wont have to stay on this too long, but my goal for myself is 130. Thats 78lbs. I'll post when I find out my weight at the month check up.

posted Feb 22nd, 2011 2:53 pm


I have been on phen for 3 weeks and have lost 9 pounds

posted Feb 22nd, 2011 1:46 pm


hi, ive taken this drug before and it has worked wonders for me it had my energy level pretty high so I was able to work out alot. I have been able to control my hunger and i lost 20lbs in two weeks just from taking this pill and power walking five times a week.

posted Feb 18th, 2011 3:57 am


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