Published on 23 November 2021

Does Venlafaxine Cause Weight Gain?

Venlafaxine (Effexor) does-venlafaxine-cause-weight-gain
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Since the late 1980s, selective serotonin reuptake inhibitors (SSRIs) have dominated the antidepressant industry. Nevertheless, the demand for antidepressants with broader mechanisms of action has grown as they may offer improvements in efficacy and side effects. Venlafaxine is an antidepressant belonging to Serotonin Re-uptake Inhibitors. It is also known as Effexor and Effexor XR. The U.S. Food and Drug Administration (FDA) approved the manufacture of Effexor in 1993. Wyeth Pharmaceuticals, Inc. Effexor was discontinued from marketing due to the severe nauseating effects.

 Effexor XR is still available by prescription and was continued as it was less disgusting and could be taken once a day. Antidepressants such as Zoloft, Prozac, Wellbutrin, and others can cause side effects such as weight gain. According to a study by SSRI, antidepressant use increases weight if the patient's lifestyle is improper, and the more you use them, the more weight you'll gain.

Does Venlafaxine also cause weight gain? If so, how does that happen? Let us see this in detail.

What is Venlafaxine?

Venlafaxine is one of a group of antidepressants called serotonin and norepinephrine reuptake inhibitors, also called SNRIs. It increases the levels of mood-enhancing chemicals called serotonin and norepinephrine. Venlafaxine is an antidepressant that affects unbalanced chemicals in the brain. 

Who Can Use Venlafaxine?

Venlafaxine treats depression, Anxiety, and panic attacks. It is only prescribed for those who are 18 years and older. If a person younger than 18 is going through the symptoms, it is necessary to get in touch with the doctor for a solution. 

How Does Venlafaxine Work?

The mechanism of Venlafaxine involves blocking serotonin (5-HT) and norepinephrine (NE) uptake pumps, with blocking NE uptake being more relevant at higher doses. It is the first inhibitor that inhibits the reuptake of both 5-HT and NE (SNRIs). In addition to increasing mood-enhancing chemicals, it boosts mental balance by increasing serotonin and norepinephrine levels. It has weak action on dopamine.

It typically takes 4 to 6 weeks for Venlafaxine to work effectively. However, it may take 1 to 2 weeks to show results in better sleep, appetite, and energy.  

It is a set of instructions regarding the dose, frequency, and administration of medication. These are necessary to acquire the maximum benefit of the drug.

You can take Venlafaxine once or twice a day. It's best to take it with food, so it doesn't make you nauseous. Do not consume Venlafaxine with alcohol, which may result in increased sedation. It comes in tablet and capsule form. 

The initial dose of Venlafaxine is 75mg per day which can be gradually increased to 375mg. The doctor may prescribe a lower dose if the patient has problems with the liver and kidney. Only use the medication in defined quantities.

Does Venlafaxine Cause Weight Gain?

Yes, Venlafexin causes weight gain. Most side effects of Venlafaxine, including weight changes, are typical of the entire SNRI class. A more likely correlation exists between Effexor weight gain and the duration of treatment than it does with treating the disorder.

How Does Venlafaxine Cause Weight Gain?

Like all medicines, Venlafaxine may cause side effects in some people. Approximately 1 in 100 people may have serious side effects when on Venlafaxine. Weight gain is one of the primary reasons people stay away from antidepressants, also known as "mood-enhancing" drugs. Many clinical trials have shown weight gain directly associated with the intake of Venlafaxine.

Some people may gain weight from Effexor within the first ten weeks of treatment, while others may develop it more gradually. The short-term effects of Venlafaxine on weight gain may be due to changes in appetite: patients eat more due to improved symptoms. There is a strong link between long-term Effexor weight gain and the drug's metabolic and hormonal effects on the body, including carbohydrate cravings and thyroid hormone effects.

Study: Venlafaxine-induced Weight Gain

In one study, more than 55 percent of patients using Venlafaxine gained weight at least 7 percent or more in a treatment that lasted 6 to 36 months. Most of these patients found it challenging to lose the gained weight due to the treatment, even after discontinuing antidepressants.

Other studies have reported similar results, where SNRIs have contributed to weight gain. It can be due to increased cravings for carbohydrate-rich foods and an increase in appetite, which can gradually increase weight. However, it does not significantly affect blood sugar levels. Venlafaxine can stimulate your appetite and can substantially impact weight.

Other variables, such as insomnia that Venlafaxine may cause, can also contribute to weight gain. Some people may feel a decrease in appetite when on antidepressants, which may lead to weight loss.    

Possible Side Effects

Using Venlafaxine may sometimes cause undesirable effects. Side effects occur with most drugs. These can be expected or severe side effects. Report any new or worsening symptoms to your doctor—some Side Effects Of Venlafaxine Include.

Common Side Effect Serious Side Effect
Headaches Cough
Dizziness Sweating
Drowsiness Muscle stiffness
Irregular heartbeat Chest pain, chest tightness
Dry mouth Skin rash
Nervousness Weight gain or weight loss
Anxiety Seizure
Sleep problems Blurred vision
Tremor Serotonin syndrome

How Can You Avoid Weight Gain From Venlafaxine?

Eating a Healthy Diet

An essential factor beneficial for weight fluctuations is eating healthy food. Various foods, including fruits, vegetables, whole grains, low-fat items, and enough protein, are essential to staying healthy and fit.  


Daily workouts can boost your metabolism and burn excess calories, which helps in losing weight.    

Getting Plenty Of Sleep

Having 7 to 8 hours of sound sleep is essential for the mind and body to reset the daily schedule. Sleeping well has proven benefits for a healthy mental and physical being. 

Precautions Before Using Venlafaxine

Precautions are essential for the safe use of drugs. It helps to avoid unwanted side effects on administering the medication. Some medications require special handling because assisting them can be risky. Known safe measures can reduce the risk of harm.

Before you take Venlafaxine

  • Take Venlafaxine as prescribed.
  • Before you take Venlafaxine, tell your doctor if you have
  • Allergy to Venlafaxine
  • consumed MAO in the previous 14 days
  • renal and or liver disorders
  • Diabetes
  • Glaucoma
  • Seizure
  • bleeding issues
  • Be careful not to discontinue taking Venlafaxine without first talking to your doctor.
  • Talk to your healthcare provider about the benefits and risks of treating depression during pregnancy.
  • Venlafaxine can pass into breast milk. If you are breastfeeding, consult your doctor.
  • Take the missed dose as soon as you remember it if you miss it. For the missing amount, do not take twice as much.
  • Avoid driving or operating heavy machinery or engaging in other risky activities until you know how Venlafaxine works.
  • Avoid alcoholic beverages if you are on Venlafaxine

Interactions of Venlafaxine

Drug interactions are every day and can be mild or sometimes severe. Doctors have to monitor carefully for any signs of reactions. If you experience any symptoms, seek immediate medical care.

Common Interactions Include

Venlafaxine increases the risk of bleeding when combined with NSAIDs, blood thinners, and antiplatelet medications. Do not start taking Venlafaxine within two weeks of finishing an MAOI, and do not stop taking an MAOI within seven days of quitting Venlafaxine unless your doctor instructs you to. Venlafaxine and an MAOI should not be taken too soon after each other to avoid potentially fatal adverse effects. These negative effects may include stiff muscles, a high fever, and uncontrolled muscle spasms.

Using medications that raise serotonin levels increases your risk of serotonin syndrome or toxicity. SSRIs like fluoxetine/paroxetine and SNRIs like duloxetine tryptophan are two examples.

Read the labels of all your prescriptions, especially those for allergies, colds, and coughs, as they can contain substances that induce drowsiness.

Avoid taking medications that include desvenlafaxine if you are using Venlafaxine.

Bottom Line From Practical Anxiety Solutions

Venlafaxine might have side effects in some people, just like any medication. Antidepressant-induced weight gain contributes to patient noncompliance with therapy and suboptimal therapeutic results. When taking SSRIs for six months or fewer, weight gain is less likely.

Increasing appetite or decreased appetite cause many patients to discontinue their medication. It may make them relapse into depression. On the other hand, it can be quite challenging to stop weight gain once it has started, so it is advisable to consider this when selecting an antidepressant. Establishing an effective physician-patient relationship begins with being upfront about the likelihood of weight gain and preventive measures.

Venlafaxine is not available over the counter; buy Venlafaxine online from a certified online pharmacy, and always consult your doctor before consuming these medications.

We can try to prevent or reduce the impact of antidepressants like Venlafaxine on our weight by applying the earlier strategies.

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