Paxil Weight Gain And Loss: Causes And Prevention

Last Updated: June 10, 2020

Authored by Roger Weiss, MD

Patients getting treatment for depression are often prescribed with SSRIs as medication. Paxil has been proven effective since 1992; however, more often than not, users are faced with another serious health issue caused by the active link between Paxil and weight gain. There are several possible causes, but luckily, most are preventable.

Does Paxil Cause Weight Gain?

While a lot of people find that Paxil works effectively against anxiety, depression, OCD, phobia, and panic disorder, like many other drugs, there are Paroxetine side effects. This potent drug is more likely to cause weight gain as compared to other SSRIs, especially during long-term treatment, approximately six months or more.

How Does Paroxetine Cause Weight Gain?

There are several ways in which Paxil drug may cause weight gain.

  • Serotonin Deficiency: Paxil side effects on weight can be attributed to the drug’s effects on hormones, including serotonin, which helps control and regulate appetite. Serotonin deficiency can cause significant weight gain.
  • Recovery From Depression: With depression, people usually have a low body mass because they’ve lost interest in food and pleasure. But, as soon as anti-depressant medications like Paxil start to kick in, they feel better and start getting a boost on appetite, which makes them eat more than usual.
  • Increased Fat Storage: The use of a psychotropic drug like Paxil may also affect the way the body processes fat. When taken for an extended period, physiological changes may ensue, leading to more fat storage.
  • Decreased Metabolism: There’s also a link between Paxil and metabolism. Despite having healthy and adequately sized meals, the decrease in metabolism and processing of food may still cause patients to round out.
  • Sweet Cravings: Patients who took Paxil were more prone to seek out unhealthy food products that contain high amounts of sugar. Though there has been a clear association between carbohydrates and the secretion of serotonin, less is known about how and which quantity of Paroxetine plays a role.
  • Drug Combinations: Certain drugs can amplify Paroxetine weight gain. Risperidone, for example, when used with Paxil can inhibit CYP4502D6 enzyme. This combination has found to increase a patient’s body mass for approximately 30 pounds within five months of treatment.
  • Side Effects: The side effects of Paxil are similar to other SSRIs, but it tends to be more sedating. It makes people feel fatigued, sleepy, and not willing to be social and active. Aside from having a motivation decrease, a sedentary lifestyle goes with it. An inactive lifestyle can increase one’s risk of obesity.
  • Sharpened Sense of Taste: Administration of Paroxetine can significantly modulate human taste perception. It increases both sweet and bitter sensitivity. This may lead to more carbohydrate cravings.
  • Withdrawal Symptoms: Patients who have stopped taking Paxil abruptly may also experience Paroxetine withdrawal symptoms. The main signs include dizziness, vertigo, headache, nausea, and flu-like symptoms, insomnia, and more. This will leave the patient feeling lazy to move as well, and there’s a big possibility of giving in to stress eating.

How Much Weight Do People Gain on Paxil?

Experts and pharmaceutical companies are advertising that drugs like Paroxetine are weight neutral, but there is evidence showing otherwise. Studies have found an association between Paroxetine and weight gain. Paxil can increase body mass when used long-term. A patient can gain as much as 24 pounds within 6-12 months of treatment with Paxil as compared to only 10 pounds with other SSRIs.

woman measuring her waist

Factors Affecting Weight Gain on Paroxetine

Several factors may affect Paxil side effects weight gain:

  • Other Medications: As mentioned earlier, the use of combination drugs may contribute to weight gain, especially if they are psychiatric.
  • Dosage: The dosage will also reflect on the drug’s effect. Doctors usually prescribe Paxil 20 mg for patients with generalized anxiety, but if it is raised, there’s a higher probability of the drug increasing body mass. Also, imbalances in the neurotransmitter levels and the nervous system are more likely caused by higher drug doses. Homeostatic processes are affected, including metabolism, which can result in weight gain.
  • Duration of Treatment: Paxil weight loss or gain is possible depending on the length of treatment. The risk of growing bigger increases as treatment prolongs. As time passes, patients are more likely leading to needing an increase in their dosage, causing further weight gain.
  • Genetics: Some gain weight quickly. The risk of obesity increases by 25% if one or both of the parents are obese.
  • Unhealthy Lifestyle: In most cases, a sudden shift to an unhealthy lifestyle along with stress, influence the occurrence of weight gain.

Paroxetine And Weight Loss

Not everyone gains weight while taking Paroxetine. Weight loss is an undesirable result of Paxil treatment, especially in the early stages. Evidence revealed a significant Paxil weight loss, an average of 1 pound, on patients in controlled trials compared to smaller weight changes in those who had a placebo.

Losing weight on Paxil can be best explained by the drug’s ability to make depressed people calmer and less anxious. They get better sleep and feel more relaxed during treatment. This improved mood usually helps bring back self-confidence and interests in doing physical activities and socializing with others. It also enhances mental health, allowing patients to make better decisions about food choices.

How to Control Weight On Paxil

There are easy tips on how to lose weight while on Paxil:

  1. Before starting Paxil for anxiety, get weighed. Be sure to record it for reference during follow-up visits.
  2. Be sure to know the difference between having an appetite and hunger. Paxil can increase one’s appetite, making a patient crave for more food without feeling hungry.
  3. A serotonin diet is a strategy that seems to work against Brisdelle weight gain. Serotonin is made after carb intake, except fructose. Sugary food, when digested, gives off tryptophan, which is used by the brain to produce serotonin. Patients are advised to take approximately 30 grams of sweet or starchy foods for breakfast.
  4. Do not mix carbohydrates and protein, or no serotonin will be produced. Protein foods interfere with the ability of tryptophan to reach the brain.
  5. Intervention is also the key. Patients with metabolic risks should see a doctor. A weight loss agent may be prescribed and monitored closely by a medical professional for weight gain. In some cases, doctors may ask patients to look for a safer alternative. It is best to make drug comparisons like at Paxil vs. Xanax.

However, weight control is not the biggest problem of paroxetine. This medication is habit-forming, and treatment for substance abuse may be required. The person in need of therapy will be enrolled in one of the numerous drug recovery centers.

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Published on: May 23rd, 2019

Updated on: June 10th, 2020

About Author

Roger Weiss, MD

Dr. Roger Weiss is a practicing mental health specialist at the hospital. Dr. Weiss combines his clinical practice and medical writing career since 2009. Apart from these activities, Dr. Weiss also delivers lectures for youth, former addicts, and everyone interested in topics such as substance abuse and treatment.


Leave a comment

  • Denise
    I am slowly weaning myself off of Paxil 30mg which I have been on for 5 years. It was prescribed for anxiety and depression by my Primary Care Doctor. Currently, I am at one quarter of a tablet once a day. Love your article, so much helpful information ! Knowing that my current dosage may not be enough is what prompted my search. I will save this publication for reference. Very helpful !
  • Jamie ervin
    Is it possible if I lower my Paxil dosage that it can help and I won’t gain as much as I have been on the higher dose???
  • Lora
    I am so angry, my doctor knows I’m struggling with my weight and she didn’t tell me about the propensity of weight gain taking Paxil. Last week I weighed 128 lbs Monday of this week I weighed 133.5 lbs and today I weighed 135 pounds. I could not understand how I could be gaining weight on 1200 calories a day, so I googled it and surprise! For those of us who are taking antidepressants to help us with hopelessness and poor self image the last thing we need to do is take an antidepressant that slows down our metabolism and causes weight gain.
    • Susan
      I, too, am furious at my doctor for not warning me about the weight gaining effects of Paxil. He should have given me the pros and cons. I feel he has only added problems that I did not have before, and my self image has made me camera shy at family gatherings and when I am out with friends. If he is so insensitive to how the side effects may exacerbate depression , he shouldn’t be treating this sensitive condition.