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Phentermine and Increased Heart Rate: What Users Say (Page 2)

Brand names: Adipex-P, Lomaira, Atti-Plex P

Reviews for Phentermine

Commonly mentioned side effects
  • Yer...
  • Taken for less than 1 month
  • December 4, 2019

For Weight Loss (Obesity/Overweight) "I was prescribed Phentermine. By day 9, I had lost 11 lbs and I was ecstatic. But that night, I ended up in the ER. My resting heart rate was 180, I was shaking, pale, and my lips were blue. They did blood work and EKG. Both came out fine. I was told to stop taking the medication and that things would get better, but they didn't. Everything I do elevates my HR. Even laying in bed, it goes up to 120 (norm is 60-100). Seven days later, I ended up in the ER again. I spent the day getting every test done: blood work, X-rays, EKGs, ultrasounds. Every test came out perfectly fine. They sent me home. But still, everything I do elevates my HR. I am exhausted, feel like I can't breathe. I am terrified to do anything because as soon as I do, my HR goes up. I need to see a cardiologist. Had I known this pill would cause all of this harm, I would have never taken it. I don't even feel like myself. I’ve been off of the medications for seven days with no improvements."

1 / 10
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  • Lis...
  • Taken for less than 1 month
  • November 13, 2018

Phentermine for Weight Loss (Obesity/Overweight) "I started Adipex on 11/8/2018. I am 5'5", I weighed in at 243 lb at the time. It is now my 5th day, and I have already lost 9 lbs. I am only taking half of the pill because the doctor thought I should gradually increase after seeing what side effects I would have. At this time, I have been following a 1200-calorie intake. Side effects have been dry mouth, blurry vision, and high heart rate, but it is tapering down now that my body is adjusting. I love the pill, but the only downside is the blurry vision. I will continue to take it to see if this stops, if not, I will just follow good eating habits and hit the gym."

7 / 10
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  • Gol...
  • June 29, 2016

Phentermine for Weight Loss (Obesity/Overweight) "So the first time I took half a pill, I had no side effects. However, the second time I took 1/2 with an empty stomach, and I had to go to the hospital. My heart was racing, and I couldn't breathe, the pain in my chest scared the shit out of me enough to stop using it altogether."

1 / 10
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Frequently asked questions

  • Mrs...
  • July 2, 2016

For Weight Loss (Obesity/Overweight) "I've been taking phentermine for 30 days now. Starting weight was 186. Current weight is 167. So happy! Didn't work out the first 2 weeks. Now I walk about 3 miles, 3 times per week. Side effects include dry mouth, constipation, and rapid heart rate. Recently experiencing stomach aches. Will take a few days off to assess what is going on. My goal is 160 pounds. Good luck, reader!"

9 / 10
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  • Cmp...
  • Taken for less than 1 month
  • January 13, 2020

For Weight Loss (Obesity/Overweight) "I took phentermine for a little over a month and lost 8 pounds. I did not have time to go back to the doctor for a refill until recently and am excited to start again. My advice is to split the full dose (37.5) in half for your first week. I tried taking the full dose right at first, and it made my anxiety awful-flushed face, headache, pounding heart, etc. Plus, if you have regular exercise and a good diet, you can make the prescription last longer and get the same results if you took a full dose without diet and exercise!"

9 / 10
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  • La-...
  • Taken for 1 to 6 months
  • December 13, 2015

Phentermine for Weight Loss (Obesity/Overweight) "I was prescribed Fastin for weight loss. The prescription pills worked great, not a single bad side effect. I lost over 50 lbs in about 4 months. It gave me energy to start working out, and WOW did my concentration for work improve. However, the pills were costly and given out in the office only. So every month it was $40 for the doctor visit and weigh-in, and another $40 for 1 month's worth of pills. When I was unable to afford this regimen, I looked for cheaper alternatives. I got some over-the-counter bottle of Fastin, I bought 2 bottles. These are unhealthy, way over-caffeinated crap! I had gotten very ill halfway into taking the first bottle and had to stop because of jitters, headache, paranoia, racing heart!!! My advice, pay for the real stuff."

9 / 10
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  • Bec...
  • Taken for less than 1 month
  • August 1, 2019

Phentermine for Weight Loss (Obesity/Overweight) "Fastin is really a great appetite suppressant! I have taken it for a few days. Yes, it does make you jittery, and your heart rate is increased, but for me, it wasn’t overwhelming. Unfortunately, the only reason I couldn’t give it a 10 is because I do feel nauseous throughout the day, which makes me not want to eat any food and drink tons of water!"

9 / 10
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  • JOh...
  • October 17, 2018

Phentermine for Weight Loss (Obesity/Overweight) "Started Adipex 9/10/18. Female - 5’9, SW 202 lbs. I have always been thinner until steroids for arthritis over the years caused weight gain. Goal is 160 lbs. My monthly check-up at the doctor on 10/6 weighed in at 191 lbs. Today, 188 lbs. I know my diet is under what I should have, usually 700-900 calories a day, light exercise. More energetic. Curbed appetite. No eating after 5:30 supper, no sweets, chicken only for fast food (no fries). If I want a mid-day snack, it’s an apple with peanut butter. One cheat day, up to 1400 calories, water only. Have dry mouth and insomnia. Faster heartbeat when active. No rage feelings. Actually, great mood because of the energy and feeling proud of myself for losing. I will gain a little back as I will have to add more calories into my diet, but have the mindset to eat healthier, and hopefully losing the weight, I will be more energetic when off Adipex. Good luck to all."

10 / 10
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  • Glo...
  • April 12, 2017

Phentermine for Weight Loss (Obesity/Overweight) "Use with caution! I was stupid enough to take a whole pill, and I thought I was going to die. My heart was racing even though I was laying perfectly still, and the world was swimming like I was drunk. The effects have lessened over the course of a few hours, but I will definitely not take more than 1/4 of one of these pills in the future!"

3 / 10
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  • Goo...
  • Taken for less than 1 month
  • July 22, 2019

For Weight Loss (Obesity/Overweight) "I tried out phentermine 15 mg for three days. The first day I didn’t notice any negative side effects, and I had no appetite at all! I had to force myself to eat. The second day same thing, except at night I felt really restless, and my heart was beating really fast and freaking me out. I already get anxiety, so when my heart was beating so fast, I felt like I had to work really hard to keep calm so I didn’t have an anxiety attack. I took a break for a day and then tried it again for a third time, and the same thing happened, at night my heart would race. It’s a bummer because it really works as an appetite suppressant. But I’d rather be hungry than feel on the edge of an anxiety attack."

4 / 10
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  • BJL...
  • Taken for 1 to 6 months
  • June 18, 2015

For Weight Loss (Obesity/Overweight) "I started taking phentermine 37.5 mg, 1 tab 2 hrs after breakfast and half a tab 6 hrs before sleep. The first day, I experienced a fast heart rate, dry mouth, and insomnia, after a couple of days, it went away. I go to the gym 3 times a week, and I have to remind myself to eat at times. I started on March 30, 2015, weighing 207 lbs, my current weight today, 06/18/15, is 179.6 lbs. I'm really happy, I don't think I have ever weighed this much since junior high. Nothing has worked for me, but phentermine sure has. Highly recommended."

10 / 10
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  • Los...
  • February 10, 2016

Phentermine for Weight Loss (Obesity/Overweight) "Started taking on 2/7/2016, as well as vitamin shots from a weight loss clinic and a 1200-calorie diet. Starting weight: 243 lbs. I am 5'5" and 30 yrs old. Since starting, I have experienced more energy, less hunger, and I have lost 6 lbs in 3 days. It is hard for me to get 1200 calories in. I do a meal replacement bar at breakfast with the medicine and a shake at lunch. Dinner is my only real meal. I have yet to find the time to get to the gym (I was going prior). I am extremely thirsty all day, my intake is in excess of 130 oz daily. Prior, I was at 60 oz. My heart rate has increased, but not to an alarming level. Will update after a full month."

9 / 10
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  • bam...
  • Taken for 1 to 6 months
  • October 30, 2015

For Weight Loss (Obesity/Overweight) "Started phentermine on 9/22/15, weighing in at 241... My first week, I lost 5 lbs. Today, I go in for my second week weigh-in... Had cut back to half a pill because heart rate was too high. I'm on a low-fat diet and no refined sugars or white flour. I work out 5 days a week. It hasn't really curbed my appetite completely, but I don't crave sweets, so that's a plus... Update.... As of 10/12/2015, I am down 14.2 lbs in 3 weeks... Feeling great. Update.... As of 10/26/2015, I am down 18 lbs... 4th week lost a lb but muscle mass went up... 5th week 3 lbs... I'm hoping Monday 11/2/2015 shows good numbers..."

10 / 10
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  • Ell...
  • Taken for 1 to 6 months
  • January 25, 2020

For Weight Loss (Obesity/Overweight) "Last year I took phentermine for 5 months. I lost 30 lbs in the first 2 months. In total, I lost 50 lbs. Beginning weight of 210, obese BMI. Side effects I experienced-when I first began, I took a half dose of 30 mg for a week because jumping right into a full capsule was too much, because it made my heart race and made me feel jittery. Throughout the whole time I took it, my mouth was ALWAYS dry, so I drank lots of water or chewed gum, mainly because dry mouth can speed up tooth decay. My jaw would feel like it had TMJ even if I hadn’t chewed for some hours. I would wake up with sore teeth as though I was grinding my teeth. I was constipated more than usual. I took the pill in the morning so I could sleep at night, it will keep you awake if you take it too far into the day. The side effects were annoying, but the weight loss was great. This medication made it so I never really felt hungry, and if I did, it would hurt my stomach to eat more than a fistful of food."

8 / 10
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  • Nik...
  • January 13, 2020

For Weight Loss (Obesity/Overweight) "I’ve taken Phentermine in the past and lost 30 pounds with no side effects. This time around, it landed me in the hospital. I started taking it on 1/5/2020 and felt fine that day and every day until 1/9/2020. That morning, I started to feel anxious. My mouth was also dry and felt like my throat was constricting. My pulse was elevated, and I was experiencing palpitations. I went to the hospital and was told to stop the medication and let it clear from my system. The following day (1/10/2020), I still had an elevated heart rate and episodes of anxiety. It didn’t feel like my throat was constricted anymore. Later on that night, I developed a crazy migraine that went away after a couple of hours. When I woke up on 1/11/2020, I had another migraine accompanied by a tingling sensation on my face. I felt like that the entire day. It was the worst feeling ever. I then started to feel tingling in my arms and legs. On 1/12/2020, I no longer felt any symptoms. My head just felt sore."

1 / 10
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  • Bet...
  • Taken for less than 1 month
  • June 8, 2015

Phentermine for Weight Loss (Obesity/Overweight) "I started phentermine on 5-26-2015. First day taking it, I got shaky, the chills, and my heart raced, but it will be 2 weeks tomorrow and those symptoms are no longer there. Unfortunately, I don't get much energy as others described, but my appetite has decreased a lot and I get fuller easily. I've lost 15 lbs so far, but I eat about 1300 to 1600 calories a day and walk every day."

10 / 10
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  • ANA...
  • Taken for less than 1 month
  • June 17, 2019

Phentermine for Weight Loss (Obesity/Overweight) "So I finally got the nerve to try Fastin. I started with only half a dose, and I felt my pulse get a little higher, but that was it. What surprised me is that it definitely works as an appetite suppressant and clearly curbs your appetite. If taken carefully, you will see success. I will post more with later results. God bless..."

9 / 10
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  • Tin...
  • Taken for less than 1 month
  • November 5, 2022

For Weight Loss (Obesity/Overweight) "Just started taking this weight loss prescription drug, and it works fabulously! Worst part is dry mouth and feeling like I need to brush my teeth excessively! My appetite is nearly gone, which allows me to choose wisely! I’m drinking safe amounts of water. I lost 10 lbs by the second week! I started at 37.5 mg and have experienced dizziness, taking deep breaths, and increased heart rate with activity, in which I’m monitoring my O2 saturation, which has remained stable at 98% with a resting pulse in the 80s. My BP has always been in the lower range, so no problem there. I’m compulsive about my smile, so I make sure to rinse my mouth out often. I’ve heard these symptoms calm down after a while. I took half a tablet today just to experiment, and my appetite is still little to nothing with fewer side effects. I suggest being mindful, for you know your body and what you can handle. So far, this is working great for me! Worst I could complain about is the dry mouth and insomnia."

10 / 10
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  • Jam...
  • June 19, 2019

For Weight Loss (Obesity/Overweight) "Took my first phentermine pill at 7 a.m., and within an hour, I felt very relaxed yet full of energy. The side effects of a racing heart and all the other negative reviews I did not experience. I have no appetite, and it's been over 10 hours since I ate breakfast. So far, no complaints!"

9 / 10
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  • Its...
  • March 10, 2015

For Weight Loss (Obesity/Overweight) "Firstly, I'm 18, 5'4", and 160 lb when I started. I've been on it for 3 days and have lost 4.8 lbs. I was going to hold off on my review, but I experienced some side effects. This takes insomnia to another level, I would go to sleep at 6-7 am just to wake up 5 hours later. These past 24 hours, I have felt so lightheaded that I stayed in bed thinking I was going to faint out of dizziness, and even while not moving in my bed after waking up, my heart would beat a thousand beats per second. I drink plenty of water too. I also had unexpected diarrhea. Needless to say, the side effects are STRONG. I love the energy boost, though."

10 / 10
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  • C_B...
  • Taken for 1 to 6 months
  • September 10, 2017

For Weight Loss (Obesity/Overweight) "SW: 260, CW: 205, GW: 160. My doctor prescribed phentermine on May 15, 2017. I have been taking half of a 37.5 mg pill in the morning and half in the afternoon. That, coupled with daily exercise and a 1,400 calorie diet, has resulted in a 55 lb weight loss in 4-ish months! There are side effects: nervousness, elevated heart rate, dry mouth, and constipation. However, these can be handled via your healthy lifestyle! Drinking about 4 liters of water a day solves the dry mouth and some of the nervousness (just always carry a water bottle with you). For the constipation, I just take fiber gummies twice a day, and it does the trick! This has been an amazing health journey! If I can do it, you can too! Keep working hard!"

10 / 10
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  • RJa...
  • Taken for less than 1 month
  • October 27, 2019

For Weight Loss (Obesity/Overweight) "41 yrs old, 5'11" and 268 lbs. I have a history of BED (binge eating) and struggled with bulimia from ages 18-30. I still, once a year or so, will binge and purge when under high stress. I started phentermine a week ago, and my results are positive. There is a decrease in appetite, I have no desire to binge eat, I drink a lot more water, I am drawn to smaller and healthier portions, and I find I have more energy. I'd rather go for a walk or organize my closet rather than sit on the couch. My sleep has not been affected, I'm not constipated, and I don't feel the nervousness or increased heart rate others experience. I'm excited to go back to my Dr. after a month and see the results from the scale."

9 / 10
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  • Tif...
  • Taken for 1 to 6 months
  • July 3, 2013

For Weight Loss (Obesity/Overweight) "I started phentermine on Feb 18, 2013. I had been going to the gym for years trying to get off this extra weight. Been overweight since I was 8 years old. I'm 24, 5'4, and got to my biggest in January (250 lbs). I've always had high self-esteem, but at that point I didn't even want to see a mirror. When I started phentermine in February, I dropped 10 lbs in 2 DAYS! No lie! Because my body was not used to the medicine, I was sweating profusely, heart racing, and had mad energy. Combined that with the gym, I was down to 235 lbs by April. Sadly, I started plateauing in April and May. I had tried everything but stayed the same. I put up the resistance in my cardio and finally lost the 5 lbs. Now it is July, and I'm out of the plateau, I am down to 220 lbs! My goal is 160/170 lbs."

10 / 10
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  • Sar...
  • September 19, 2017

For Weight Loss (Obesity/Overweight) "LOVE THIS! Wish I'd tried it sooner, still have another week till I hit my 3 months & lost over 60 pounds. (not exercising at all) 484 lb to 423 lb and still losing pretty steadily!! My only side effects are increased heart rate sometimes when I'm just sitting or some days I completely forgot to eat... so I took some re-learning to get used to. It gave my stomach the time to shrink (which I normally cannot do during a diet) and I can eat normal portioned meals and feel completely satisfied (how I assume normal people feel). It's a whole new world, and I could not be more happy with the results! I lost 10% of my body weight so far & extending pills for 3 more months! If you're on the fence, definitely try it, could be the best thing you do for you!"

10 / 10
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  • Cry...
  • June 22, 2019

Phentermine for Weight Loss (Obesity/Overweight) "Got these pills and took a pill after breakfast, and my heart felt like it was going to pop out of my chest. Increased heart rate, blood pressure. Also gave me a terrible headache and nausea. Felt like I was going to die. Had to go to the hospital, and the doctor told me I was getting an anxiety attack as well. Would not recommend it. Terrible experience."

1 / 10
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Reviews may be edited to correct grammar/spelling or remove inappropriate content. Reviews appearing to come from parties with a vested interest are not published. This information is not intended to endorse any medication and should not replace the expertise and judgment of healthcare professionals.