Celexa (Citalopram) is a drug that is commonly prescribed for the treatment of depression. It works as an SSRI (selective-serotonin reuptake inhibitor) which increases extracellular levels of serotonin. It is believed that by increasing serotonin, it is an effective treatment for major depression as well as various forms of anxiety and panic disorders. It has been around since 1998 and is still regarded as a very popular antidepressant treatment.

Despite the fact that many people get relief from depressive or anxious symptoms while taking this drug, many people experience unwanted side effects. Perhaps the most obvious and difficult side effect to deal with is that of weight gain. Packing on a few pounds isn’t generally considered a big deal, but some people end up packing on more than just a few as a result of the treatment.

Celexa and Weight Gain

There is research showing that anyone taking SSRIs like Celexa for a long term (e.g. 6 to 12 months) will likely gain some weight. Not everyone will gain a significant amount, but the fact is that certain individuals gain so much weight, that the weight gain itself becomes a source of depression and anxiety. This ends up becoming a Catch-22 – treat the original symptoms, but gain weight and feel depressed and anxious about it.

How Celexa Causes Weight Gain: List of Theories

There hasn’t been much scientific research conducted as to why antidepressants, particularly SSRIs like Celexa cause people to gain weight. In the past, most patients were told that Celexa won’t cause any weight gain. Now, we know that it probably will, but most professionals don’t really know why. Below are some possibilities of how this drug causes people to gain weight.

  • Appetite increase: A number of people may be so depressed prior to taking Celexa that they experience a poor appetite and/or don’t eat much. When the drug starts working, they may become hungrier and start eating more meals. The amount of appetite increase that a person experiences is subject to individual variation.
  • Body’s fat storage: It is possible the mechanism by which the body stores fat becomes altered when a person takes an SSRI. This leads to some people experiencing an increase of body-fat in places such as the stomach, chest, and/or hips. While not everyone accepts this theory, it is still a possibility.
  • Carbohydrate cravings: Many people start taking Celexa and notice that they crave carbohydrates. Since there is a clear link between the neurotransmitter serotonin and carbohydrates, some speculate that the drug-induced serotonergic alterations are responsible for making some people crave carbohydrates. If you start eating junk food, sugary food, or develop cravings after you start the drug, it’s probably a byproduct of the Celexa.
  • Drug interactions: If you are taking other medications (or drugs), the Celexa may be interacting with it to further increase weight gain. Those taking an antipsychotic along with an SSRI often notice this to be the case. Some drugs work synergistically to alter homeostatic functioning and can significantly slow metabolism.
  • Hormonal abnormalities: In some cases, it is believed that Celexa is capable of altering hormone levels. As a person continues long-term treatment with this medication, it is possible that the drug changes levels of certain hormones, which causes weight gain. When our bodies don’t produce adequate amounts of certain hormones and/or produce excess amounts of other hormones (e.g. cortisol), it’s easy to gain weight.
  • Improved taste: Many people notice that their tastebuds perk up when they take an antidepressant. This leads them to enjoy food more than prior to being medicated. The improved taste may lead to more frequent snacking and food consumption than in the past.
  • Motivation deficit: It’s possible to become less motivated when taking medications. Many people taking antidepressants have a tough time getting to the gym or even getting some basic exercise because the drug depletes their intrinsic motivation.
  • Side effects: Certain side effects from this drug may lead someone to become lazier than usual. If you feel lethargic, sleepy, sluggish, or drowsy after you take this drug, chances are that you’re not in any hurry to get out of bed, let alone get physical activity. The side effects alone can make a person so tired, that they have a difficult time staying active which leads to a slowed metabolism.
  • Slow metabolism: A well-accepted theory is that when a person takes an SSRI, it slows a person’s metabolism. This means that even if a person is eating the same diet they were prior to taking Celexa, they are going to experience some weight gain. If you are exercising and eating healthy, but are still packing on pounds, it’s likely due to a metabolic alteration.
  • Social eating: Those that find this drug helping their depression and/or anxiety may start doing things with friends and co-workers. One such activity that they may take up is that of social dining or going out to eat with others. While going out to eat isn’t bad if healthy foods are selected, most people order comfort foods when eating with others. Continuous social eating is often a fast-track method to gain weight.

Note: The above theories are all possibilities as to how Celexa may contribute to weight gain. Keep in mind that one specific change such as slowed metabolism may cause you to gain weight, but a combination of changes is the more likely cause.

Factors that influence weight gain on Celexa

There are a variety of factors that influence the amount of weight you’ll gain from taking Celexa. Keep in mind that these include individual factors like genetics, the dosage you’re taking, how long you’ve been on the drug, as well as interactions with other drugs.

1. Dosage

The drug comes in 10 mg, 20 mg, and 40 mg tablets. Those that are taking a relatively high dose like 40 mg are more likely to gain weight. The more you increase your dose of a drug, the more changes it elicits upon your physiological functions. Each time you increase your dosage, you also increase the potential (and possibly the amount) of weight gain. If you are taking a low dose such as 5 mg or 10 mg, you may not gain any noticeable weight.

2. Individual factors

There are a variety of individual factors that will influence how much weight someone could gain on this medication. These include things like: environmental stress, baseline metabolism, genetics, hormones, sleep patterns, dietary intake, exercise, and habits. Those who eat healthy foods and get plenty of exercise may be less likely to gain significant weight.

People who don’t get sufficient sleep, eat a lot of carbohydrates, and don’t exercise are thought to gain more weight. It is always important to consider the efforts you are making to keep your weight healthy. You may also want to consider checking out GeneSight, a test that analyzes your genetics to determine how well you’ll tolerate Celexa.

3. Time span

The duration over which you have been taking Celexa plays a role in determining whether you’ll gain weight. Those who take the drug for a short-term (e.g. a few months) may not gain any weight. Some studies show that most people gain weight after they’ve been taking this drug for 6 to 12 months.

This is likely due to the fact that the body has become increasingly reliant on the drug and certain homeostatic functions have been altered. Most people also notice that their antidepressant stops working as a result of tolerance when taken over the long term. This typically leads to an increase in dosage, which is known to further increase weight gain.

4. Other drugs/medications

Always think about the effect of other medications (besides Celexa) on your weight. If you are taking any other drugs, they may be interacting with Celexa to increase the amount of weight you gain. If multiple medications are slowing your metabolism, the cumulative weight gain resulting from combined treatments may be even more significant than just taking one or the other.

Individuals that suspect multiple medications are causing an increase in weight may want to talk to their doctor about alternative strategies. Figuring out which drug is having a greater impact on your weight is often tricky, but may be worthwhile if you can afford to stop one of the treatments.

How much weight will you gain from Celexa?

Many studies suggest that compared to other SSRIs, Celexa seems to be the least likely to cause weight gain. Those that take the drug for just a short-term (e.g. less than 6 months) may actually lose weight or remain weight neutral. In general though, those that take any SSRI medication for over 6 months are likely to experience some weight gain.

Experts suggest that the amount of weight gained is an average of 10 lbs. over the course of SSRI treatment. Another study found that people gained an average of 15.7 lbs. after just 2 months of treatment. There appears to be conflicting evidence in regards to how much weight you’ll gain (on average) from this drug.

Will everyone gain weight while taking Celexa?

Not everyone will gain weight while taking Celexa. Those that are taking adjunct treatments (e.g. stimulants) that increase activity in the central nervous system may gain no weight. Others that take particularly astute care of their dietary intake and exercise habits may not gain much weight from this drug. Some studies suggest that 1/4 individuals taking an SSRI will gain weight. However, if you’re on Celexa for a long-term, some weight gain is likely inevitable.

Celexa: Cost-Benefit Analysis

When taking any drug, it is important to evaluate the efficacy of the treatment and compare it to the drawbacks that you’re experiencing. In other words, analyze the benefits (degree of efficacy) and compare it with the costs (side effects). If Celexa has stopped working or isn’t working well, plus you are gaining weight, it may be worth considering another medication and/or pursuing Celexa withdrawal. If this drug is working well, and you only gained a little weight, the little bit of weight is likely a fair tradeoff for the significant improvement in mood.

Did you gain weight while taking Celexa?

Although not everyone will pack on excess weight while taking Celexa, it would be nice if the people who gained weight could share their experience. Feel free to discuss what you think caused you to gain weight, what dosage you took, how long you had been taking Celexa, etc. Sharing your story may help someone else relate who may have also experienced the inevitable, dreaded weight gain associated with SSRI medications.