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Lorcaserin and Fatigue: What Users Say

Fatigue: mentioned by 55 users (5.9%)

Based on user experiences from 939 Lorcaserin reviews, the following table shows the most commonly mentioned side effects.

All user comments are moderated by Drugs.com. Each review is verified for relevance and screened for inappropriate content. Side effects are user-reported and not clinically verified.

headaches 24.2%
tiredness 12.9%
dry mouth 9.3%
dizziness 8.6%
fatigue 5.9%
nausea 5.8%
chills 3.7%
body aches 2.1%
brain fog 2.0%
drowsiness 1.9%

Reviews for Lorcaserin

Commonly mentioned side effects
  • Fun...
  • Taken for 6 months to 1 year
  • May 20, 2014

For Weight Loss (Obesity/Overweight) "I was always the funny fat guy with few dating deals. Well, my health last year was not funny, and now the best thing that could happen is my gradual weight loss. I am losing about seven pounds a month, and after nine months, I am on my way. My health has improved on all fronts with just fatigue as the only side effect, and that passed quickly."

10 / 10
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84 Report
  • los...
  • May 20, 2014

For Weight Loss (Obesity/Overweight) "Started this less than a week ago. Only side effects have been some fatigue and dry mouth. The dry mouth has caused me to drink more water which is good for anyone. I started at 214 and am already 210. I feel full far sooner than before and don't feel the cravings I would always get during the day. Hopefully, the fatigue will pass next week. Recheck with doctor on 6/2... can't wait! Sadly, I'm a lapband failure and never get the 'I'm full' feeling with it, so this is promising!"

10 / 10
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78 Report
  • Dwi...
  • July 6, 2016

For Weight Loss (Obesity/Overweight) "I was prescribed Belviq about three months ago - April 2016, 10 mg twice a day. I went to the doctor two months later and had lost 15 lbs, from 266 to 251. Again, I went two weeks later and I was down to 246. I had some side effects such as fatigue and dry mouth, but I just drink more water. It does a great job of curbing my appetite, making me feel full on less food. It also seemed to change my taste buds. It doesn't agree at all with alcohol. This is the first drug that has helped me lose weight. This is important since I am on estrogen blockers due to breast cancer and had a hard time losing weight. I will continue on this medicine."

8 / 10
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61 Report
  • Blu...
  • August 18, 2015

For Weight Loss (Obesity/Overweight) "I have only been taking Belviq for 6 weeks, and I have already lost 5.4 pounds. I only take one pill a day. I do feel a little fatigue, but I can deal with that! Also, a little dry mouth, but this increases my water intake. This medicine is an answer to prayers. I am never hungry, and when I do eat, I eat less than 1/2 of my food."

10 / 10
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54 Report
  • Chr...
  • Taken for less than 1 month
  • May 19, 2014

For Weight Loss (Obesity/Overweight) "I have been on it for 16 days now. Lost 17 lbs. I’m 50 years old, 6’0” tall and weighed 245 lbs, currently weighing in at 227/228. My only side effects were dry mouth, which is not too bad, considering my lack of water intake. Another was great sleep. You have to watch yourself because you have to force yourself to eat. If not, you can have a lack of energy, slight lightheadedness. When I do eat, I find myself eating much healthier, cutting back on beef and carbs. My plan is to stay on it until I reach my goal of 200 lbs. I’m hoping I can achieve my goal in the next 3-4 weeks. The manufacturer has a free 15-day trial, so you can try it and see how it goes! I highly recommend Belviq. Good luck!"

10 / 10
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60 Report

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  • Hea...
  • Taken for less than 1 month
  • July 3, 2015

For Weight Loss (Obesity/Overweight) "I've been on B for about 2 weeks and lost 5 lbs. I'm not doing anything extreme diet-wise... eating calories based on BMR and plan to exercise more regularly next week. I've had a mild cough, fatigue, and body aches, but I hear it'll subside. It's worth it right now. I seem to have more awareness, self-control, and get full faster. I have hypothyroid, and losing weight was always hard for me, even with crazy programs and costly supplements. For the first time in forever, I feel in control of what I'm choosing! I know it will be a long journey, but I'm ready."

9 / 10
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54 Report
  • Anonymous
  • June 22, 2015

For Weight Loss (Obesity/Overweight) "I started Belviq about 9 days ago. I found a savings card online on the Belviq website that will save me approximately $140 each time I fill my prescription. I have experienced a significant mood lift (I can see why it's a controlled substance), subtle drowsiness, and better sleep. Sometimes I forget to eat because I just don't feel hungry. I feel the effects of not having eaten, though, I feel tired, sluggish, and my stomach hurts a little from being empty, but the terrible 'hunger' feeling is completely missing. It's strange, but extremely helpful. Overall, I have lost 6 lbs in the last 9 days since I started Belviq, and it surely is helping with my appetite. I am very thankful. Belviq does exactly what it's supposed to."

9 / 10
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50 Report
  • cmp...
  • Taken for less than 1 month
  • September 2, 2013

For Weight Loss (Obesity/Overweight) "The good: I've been taking Belviq for two weeks. I have had a significant decrease in appetite and desire to eat. Even when I am hungry, I'm really not interested in food. I get up to find something to snack on, but find myself walking away because nothing looks good to eat. I've had a 7-pound weight loss, so I would call this a success. The bad: I have definitely noticed the fatigue, all day long. My mood is pretty flat all of the time. Not happy, not sad, just flat. I have been dizzy, at times to the point of needing to sit down. I also notice difficulty keeping my eyes focused on the screen. Like my eyes are drifting without my being able to control it. I'm thinking about stopping or lowering the dose."

6 / 10
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72 Report
  • Jil...
  • Taken for less than 1 month
  • May 29, 2015

For Weight Loss (Obesity/Overweight) "I started the pill, and the first day was super wacky and dizzy. After the 10th day, I discontinued. I had gained weight; had water weight but was dehydrated; had blurred vision; dizziness, headache, backache, and joint/muscle aches; couldn't complete a sentence; chills, shakiness, vivid dreams; couldn't drive; extreme fatigue and disassociation. I think I had serotonin syndrome. I was not successful on it, but the patient insert was helpful, and I realized I needed to get off of it. After stopping taking it, I started feeling better by the hour. Now, two days late, every symptom has gone away. I have about 40 lbs to lose. I am happy for those who found success with Belviq but wanted to post my experience for those who are having trouble."

1 / 10
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55 Report
  • Gai...
  • June 13, 2016

For Weight Loss (Obesity/Overweight) "I started Belviq and did get headaches and fatigue the first week, then it went away. I sleep so well when I take it at night and am not tired anymore with my first dose in the a.m. I have lost 16 pounds by drinking a lot of water and watching what I eat. I love this pill - I would never take anything for weight loss, but I will stay on this one to reach my goal. I was 192 lbs, 5'1'' on May 9th, and down to 173 on June 13th."

8 / 10
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42 Report
  • Ang...
  • Taken for 1 to 6 months
  • August 5, 2017

For Weight Loss (Obesity/Overweight) "I've been taking 10 mg of Belviq 2x a day for 4 weeks. The first few days, I had headaches. They went away, and then the next, I had a ringing in my ears and loss of balance (can't say that is a side effect or a coincidence). They went away as well. I have had no side effects since then, other than fatigue and weight loss!! Belviq has made it easier for me to cut calories and not feel hungry. It has also made it easier for me to ignore people eating around me. I don't crave anything anymore. When I started on July 10th, I weighed 186 lbs, and now on August 5th, I weigh 172. 14 lbs and counting. Also, my insurance wouldn't cover it, but I got the manufacturer's coupon (which was really easy), and I use that and only pay $83.00. I say stick with it!"

10 / 10
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38 Report
  • Jua...
  • Taken for 6 months to 1 year
  • May 5, 2014

For Weight Loss (Obesity/Overweight) "Simple started out 5'6", 188-pound male last September. Had some fatigue and dry mouth, but drank more water and it seemed to ease those issues after a few days. Now I am at my goal of 140 pounds and ride my bike three times a week. My doctor says my numbers are good and to keep up the good work. I am staying on my full dose as I don't want to gain my weight back like before. Just feel really healthy."

10 / 10
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50 Report
  • Pat...
  • August 5, 2017

For Weight Loss (Obesity/Overweight) "I started Belviq on May 10th. I have lost 20 lbs since, today being 8/5. I wanted something to aid in my weight loss, being 200 lbs, 5'2", 52 yrs old. I asked about Contrave, but my doc suggested Belviq because of patient success. I had nausea and a headache for 3 days, but that went away. I also had a nagging cough for a couple of months, but that went away, also. The only other notable symptoms are occasional sluggishness and brain fog. I take two 10 mg pills a day. I know when the first one's wearing off because I do get hungry. It does curb my appetite really well, and I have to force myself to eat. I have the most success when I work out, too, and cut down on sugar and food intake, which Belviq aids in. I love it!"

9 / 10
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32 Report
  • DCi...
  • Taken for less than 1 month
  • August 6, 2015

For Weight Loss (Obesity/Overweight) "I've been on Belviq for about 12 days. The side effects the first week were a little rough: severe dry mouth, body aches, dizziness, fatigue, and I actually gained 3 lbs! But if you can get through that, the 2nd week has improved. The side effects have mostly disappeared, with the exception of the dry mouth. I have lost the initial 3 lb gain and am down 3 more! I'm never hungry and have to remind myself to eat. When I do eat, I'm fuller faster! My insurance didn't cover it, so I downloaded the 15-day free sample and the savings card from the website, and so my cost will be $75 a month. I'm planning on staying on this pill and will keep you updated on the progress. I'm pretty excited now that I'm seeing the weight loss!"

7 / 10
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36 Report
  • the...
  • December 10, 2014

For Weight Loss (Obesity/Overweight) "I can say that it works as far as suppressing your appetite, but I have only been on it for one day, and I am waiting for it to leave my system. I don't like the warm sensation over my body, and a few chest pains, very sleepy and sluggish feeling, so for those reasons, I will not be taking Belviq anymore."

2 / 10
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62 Report
  • ple...
  • Taken for less than 1 month
  • October 26, 2014

For Weight Loss (Obesity/Overweight) "It works. I have lost 10 pounds so far. Starting week 4. I could have lost more if I could get my love of beer under control. The first few days were tough, serious nausea in the morning after taking the pill, also felt very mild depression and fatigue. Subsided in 2-3 days. Feel no side effects now. I still have an appetite but not as much as prior to starting Belviq. Breakfast: fruit. Lunch: small sandwich or salad (easily turn away from chips or sweets). Snack: apple. Dinner: salad or small meal. Staying under 1800 calories per day. I've been keeping a food journal, which has been eye-opening how many calories are in my daily intake. I feel like this will work for me, but will be a long process."

8 / 10
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36 Report
  • Anonymous
  • Taken for less than 1 month
  • April 3, 2016

For Weight Loss (Obesity/Overweight) "Been taking Belviq for 3-4 weeks. Side effects were mild headache, fatigue, and sneezing in the 3rd week, but now subsided for the most part. I am, though, a little tired at the end of the day and sleep well at night. I'm assuming the longer you take it, the more your body gets used to it. I have lost 15 lbs so far. I have cut my portions to almost half. Still eating much of what I like, but less. Also, notice that I have made some new healthy choices. I plan to start exercising this week as well, by walking regularly until I can jog comfortably. I know there is no perfect pill that's not going to have side effects, so if there's a little discomfort in the short term for long-term gains, I'm in. I truly believe Belviq will help me achieve my long-term goal."

9 / 10
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31 Report
  • TLj...
  • October 11, 2016

For Weight Loss (Obesity/Overweight) "I've been taking Belviq for 3 months. I've gone from 182 to 171, but multiple health issues make me a slow loser. I'm not following a formal diet, just eating less. I had a bad headache, fatigue, and a weird tingling sensation all over my torso for the first 2 days, then no more side effects. I started with 1 pill the 1st week, then 2 pills a day. It makes my appetite normal. I get hungry, I eat a reasonable portion, then feel full and lose interest in eating more. I think naturally thin people do that - get full. Not wanting to eat continuously or binge is a new experience for me. I love Belviq, but they've just stopped the $75 coupon. Now, it's $200 off, which makes it $100 a month for pills. I may switch back to one a day and hope it works."

9 / 10
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27 Report
  • Bac...
  • Taken for less than 1 month
  • October 25, 2017

For Weight Loss (Obesity/Overweight) "I used Belviq two years ago for about 4 months, and I lost 25 pounds. I weighed 185 when I started on the pill. My weight dropped to 160 in less than 4 months. I'm 60 and 5'4". At first, I experienced slight dizziness and felt sluggish and sleepy. After taking vitamins (B12, calcium, multivitamins), it went away. I stopped taking it after I reached my goal. However, I started to gain the weight back after 2 years to 192 lbs. A whopping 32 pounds gained! I got back on Belviq on October 6. After 3.5 weeks, I lost 14 lbs. with no exercise. I got the same side effects, but they all went away after the first week. I plan to do a little bit of walking and light exercise just to speed up the weight loss and get used to the routine after I'm off the pill."

10 / 10
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25 Report
  • Jar...
  • Taken for 1 to 6 months
  • March 30, 2016

For Weight Loss (Obesity/Overweight) "I've been taking it for about 6 weeks. I've lost 7 lbs so fast. The fatigue is awful, though. Yes, I'm finally sleeping all night, but I'm still tired all day. I'm going to continue to take it as long as I keep seeing the weight drop. It's not going to make you drop 10 lbs a week. You also have to be in the right mindset to be ready to eat better, also."

7 / 10
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25 Report
  • Ali...
  • May 25, 2016

For Weight Loss (Obesity/Overweight) "So far, it is working very well. It is curbing my desire to reach for more than one portion at a time. It is allowing me to eat less and think twice about what I am consuming. The fatigue is present, but you have to consider the drop in food intake and the medication. I am doing the Atkins diet, taking supplements, and exercising when I am able to. Headaches disappeared after the first day. Definitely worth it for me. Print out the coupon, it will help to offset the expense of the medication."

8 / 10
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24 Report
  • Der...
  • March 5, 2019

For Weight Loss (Obesity/Overweight) "Day 3 of Belviq, appetite curbed. Down 2 pounds. As far as side effects, I am experiencing extreme fatigue, thirst, and cold chills. Hopefully, they will pass within a few weeks. Had to pay $130, so I am going to give it a fair try. So far, it seems to be doing what it should. Now, if I can get over being so dang tired."

8 / 10
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17 Report
  • Mag...
  • Taken for 1 to 6 months
  • June 25, 2018

For Weight Loss (Obesity/Overweight) "I started taking Belviq XR in January 2017, had to stop for a month because I had a knee replacement and needed to take strong opioids, which don't mix, then went back on Belviq in March 2017. I have taken the drug for almost 5 months (two months a gap, then three months) and gotten over most of the side effects. The first two to three weeks both times were bad: extreme exhaustion and nausea, no headaches. Since then, I just get fatigued mid-afternoon and sleep about an hour more than pre-Belviq. I've lost about 25 lbs since I started, which is slow and steady, and plan to lose another 20 before I stop taking it. I do use the Belviq manufacturer coupon as my insurance does not cover the cost. The coupon cuts the cost in half. You can find the coupon on the Belviq website."

10 / 10
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17 Report
  • Mag...
  • Taken for 1 to 6 months
  • June 25, 2018

For Weight Loss (Obesity/Overweight) "I started taking Belviq XR in January 2017, had to stop for a month because I had a knee replacement and needed to take strong opioids, which don't mix, then went back on Belviq in March 2017. I have taken the drug for almost 5 months (two months a gap, then three months) and gotten over most of the side effects. The first two to three weeks both times were bad: extreme exhaustion and nausea, no headaches. Since then, I just get fatigued mid-afternoon and sleep about an hour more than pre-Belviq. I've lost about 25 lbs since I started, which is slow and steady, and plan to lose another 20 before I stop taking it. I do use the Belviq manufacturer coupon as my insurance does not cover the cost. The coupon cuts the cost in half. You can find the coupon on the Belviq website."

10 / 10
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17 Report
  • Mom...
  • Taken for 1 to 6 months
  • July 17, 2019

For Weight Loss (Obesity/Overweight) "I started taking Belviq 2x a day in Feb 2019, weighing 209 lbs, paying out of pocket $145 a month with the savings card on their website. I have severe headaches, I get grouchy and irritable near time to take it again, I have severe fatigue, and a general sense of not feeling well. I ache and stay sore in my muscles, and have severe cramps in my legs and feet. Here it is July 17, 2019, and I weigh 212 lbs. This product has not had any positive weight loss results for me, and after this bottle is out, my doctor will be taking me off of it. I do not know what will work for me, but I am disappointed in these results."

1 / 10
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14 Report

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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.