Venlafaxine: A review

In this guide, we will discuss Venlafaxine: A review of the pharmacology and therapeutic potential benefits for patients, possible side effects, warnings, and precautions.  

Venlafaxine: A review of its potential benefits

The article “Venlafaxine: A review of its pharmacology and therapeutic potential in depression” showed how administering Venlafaxine 75 to 375 mg/day for 6 weeks in patients with major depression was significantly more effective than placebo. 

Venlafaxine (generic name), for a “phenylethylamine derivative which facilitates neurotransmission in the brain by blocking presynaptic reuptake of serotonin (5-hydroxytryptamine: 5-HT) and noradrenaline (norepinephrine)”. Venlafaxine is alos known as Effexor.

Additionally, Venlafaxine has been shown to be well tolerated and associated with fewer side effects when compared to tricyclic antidepressants. 

However, there have been a few reports of increased blood pressure when the drug is administered in high doses.

Venlafaxine is also known by the brand name Effexor and it is commonly the most prescribed antidepressant considered an SNRI or Serotonin-norepinephrine Reuptake Inhibitor usually prescribed to treat anxiety disorders, specifically Generalized Anxiety Disorder (GAD), panic disorder and social anxiety disorder (SAD). 

Moreover, it is also prescribed off-label as migraine, diabetic neuropathy, and hot flashes treatment.  

Another study showed that in patients with depressive disorders, venlafaxine was more effective than SSRIs or Serotonin-reuptake Inhibitors. 

What is Venlafaxine?

Venlafaxine is an antidepressant medication that works to minimize depressive symptoms thanks to its chemical properties in minimizing the occurrence of depression.

This medication has been used in other psychological which makes it an over-the-counter medication for these afflicted people. 

Venlafaxine has been used to treat psychological disorders such as depressive disorders, panic disorder, and anxiety disorders.

This medication is taken for two to four times a week.

Venlafaxine is safe to take with food if you prefer.

The dosage that you will be prescribed with this kind of medication will be based on your psychological treatment and the severity of your depressive symptoms. 

Venlafaxine takes approximately 4 to 6 weeks to work just like other antidepressant medications.

If you want to finally stop these kinds of medications, you need to tell your doctor about this kind of concern and they will reduce your dosage of this medication which occurs gradually to avoid adverse side effects.

What is venlafaxine as antidepressant medication in psychological treatment?

Venlafaxine is an antidepressant medication that is considered to be grouped under the class of the serotonin-norepinephrine reuptake inhibitor medications.

Being in this class of medications makes this antidepressant medication to treat depressive disorders and some anxiety disorders such as panic disorder, generalized anxiety disorder, and social anxiety disorder. 

Venlafaxine has been used as pain-relief medications which are off-label uses of this medication to treat migraine, hot flashes, and diabetic neuropathy.

There are adverse side effects that can occur after the usage of this antidepressant medication with these off-label uses such as vomiting.

What is venlafaxine xl as a brand name?

Venlafaxine Xl as a brand name was called Effexor XR that was used to treat depression.

This medication has been considered as effective in some studies when used as maintenance treatment for depression. 

Effexor which is the brand name of venlafaxine was also discovered to be effective for people with a social anxiety disorder.

This was discovered in studies that were using experimental trials for the effects of this antidepressant medication.

What is the Vensir xl available in the NHS?

Vensir Xl is available in the NHS to treat people with major depressive episodes.

In adults, the average initial dosage of 75 mg has been used to treat some symptoms of these depressive episodes and was increased to 150 mg per day. 

When the patient is having severe symptoms of major depressive disorders, they will be prescribed with the maximum dosage of Vensir Xl which is 375 mg.

You should be aware that this medication is only prescribed to patients with depression and not anxiety which may cause adverse side effects if used for this psychological disorder.

Nevertheless, they are a lot of patients with anxiety that have been using Vensir Xl. in this case, the usage of this medication for an anxiety disorder is considered off-label use. 

Due to the risk of getting adverse side effects, doctors would prescribe specific dosages of Vensir Xl if the patient with an anxiety disorder has been thoroughly clinically assessed.

Patients should be using this medication after several months or longer than using this medication in a short period of time.

The withdrawal of Vensir Xl

As mentioned before, Vensir Xl has venlafaxine hydrochloride which makes it effective in treating major depressive disorder.

Also mentioned was the need to gradually reduce the dosage of this medication when the patient wishes to stop this antidepressant medication. 

If there are depressive symptoms that are making the patient uncomfortable, this will make the doctor advise the patient to take the same dosage as done before.

If these symptoms have been minimized, the doctor will continue in decreasing the dosage of Vensir Xl to make you safely stop this antidepressant medication. 

The doctor would highly suggest that the patient takes Vensir Xl with food but they should take it in the same period of the day whether breakfast or lunch.

If you don’t see the effects of this medication to major depressive disorder, you need to ask your doctor on the right action. 

Vensir Xl is one of the considered antidepressant medications since it has fewer uncomfortable side effects than other antidepressant medications. 

How does it work?

Venlafaxine works by increasing and regulating the levels of serotonin and norepinephrine in the brain.

It is said that at low doses, Venlafaxine can prevent serotonin reuptake, meaning that it can leave more “free” serotonin.

In the usage of higher dosages of this kind of medication, it lessens the occurrence of the reuptake of serotonin and norepinephrine. 

What are norepinephrine and serotonin mean to psychological abnormality?

Norepinephrine or noradrenaline as it is best known is a stress hormone that has the ability to affects those parts of the brain associated with response and attention.

It is also responsible for increasing your heart rate, triggering the release of glucose and increase the blood flow to our muscles to prepare for the “flight or fight” response when in the presence of a perceived threat or harmful situation. 

On the other hand, serotonin is a neurotransmitter known to affect psychological abnormality that helps controlling several processes such as mood, emotional responses, anxiety, and aggression, appetite, sleep, and memory, among others. 

How should I take Venlafaxine as an antidepressant medication?

This drug is available as tablets which are usually prescribed to be taken 2 or 3 times a day with food and as an extended-release (XR) capsule that is usually recommended as a single dose daily in the morning or evening with food. 


Under the brand name Effexor, only the extended-release form is available and the generic form has the two options available (as tablets and extended-release form). 

How is venlafaxine used as an antidepressant medication in the UK?

Venlafaxine is an antidepressant medication has been used in the UK to cure the symptoms of an afflicted patient’s major depressive disorder symptoms.

Although this antidepressant medication has been used to heal those people with a generalized anxiety disorder as well. 

Venlafaxine has also been an effective psychotropic medication for people with panic disorder with or without agoraphobia.

This antidepressant medication works by interacting with the neurotransmitters called serotonin and noradrenaline which the heightening of these neurotransmitters can help regulate depression.

Venlafaxine is not prescribed to patients with other treatments they have been taking due to an existing medical condition.

This is why your doctor should know about your recent medical history to know what treatments have you been taking before venlafaxine since some medications negatively affect this antidepressant medication. 

Venlafaxine has also been used as an initial intervention for people with cataplexy.

Cataplexy is a symptom of narcolepsy which is a sleeping disorder where you have a hard time trying to wake up when you are doing an important activity such as driving.

Dosage and drug interaction 

According to, the usual dose is 37.5-375 mg daily.

Effexor may interact with other medicines that make you sleepy such as:

  • cold or allergy medicine,
  • sedatives,
  • narcotic pain medicine,
  • sleeping pills,
  • muscle relaxers, and
  • medicine for seizures or anxiety,
  • nonsteroidal anti-inflammatory drugs (NSAIDs),
  • monoamine oxidase inhibitors (MAOIs),
  • cimetidine,
  • ketoconazole,
  • linezolid,
  • lithium,
  • haloperidol,
  • risperidone,
  • tramadol,
  • L-tryptophan,
  • warfarin,
  • almotriptan,
  • frovatriptan,
  • sumatriptan,
  • naratriptan,
  • rizatriptan,
  • zolmitriptan, or
  • other antidepressants

Always let your doctor know about any medications and supplements you may be currently taking so he/she can advise how to proceed and avoid any drug interactions. 

Side effects of Venlafaxine

According to pharmacists, the following are the side effects of venlafaxine:

  • Dizziness
  •  Nervousness
  •  nausea 
  • Constipation
  •  Headaches
  • Anxiety
  •  Insomnia
  •  strange dreams
  • Drowsiness
  •  increased sweating
  •  blurred vision
  •  dry mouth
  • Dramatic changes in appetite or weight
  • receded sex drive
  • Impotence
  • Difficulty reaching or having an orgasm
  •  enhanced blood pressure
  • seizures

The immediate avoidance of Effexor will cause the following discontinuation symptoms:

  • dizziness
  • headache
  • nausea
  • Significant changes in mood state
  • Dramatic changes in the sense of smell and taste

What are the side effects of Xl medical of Venlafaxine?

The following are side effects of the Xl medical version of venlafaxine with common side effects and chronic side effects

Typical side effects of Xl medical

As mentioned in the name, these are the side effects of Xl medical that occur in most afflicted patients.

You need to tell your doctor immediately if you are feeling the following side effects whether it’s only one or two of them you are experiencing:

  • feeling sick
  • headaches
  • sweating
  • dry mouth
  • trouble sleeping
  • feeling dizzy
  • feeling sleepy
  • constipation

Chronic side effects of Xl medical

Although not typical, some people would experience the chronic side effects of Xl medical which are the following.

  • Weight gain or weight loss with no behaviours causing it
  • Manic mood
  • Yellow skin
  • Muscle fatigue without any known causes
  • Alterations in your eyesight such as seeing only near objects or far objects
  • Bleeding from your gums
  • Vomiting blood or dark puke
  • Suicidal thoughts

Chronic allergic reaction cause by Xl medical

Anaphylaxis is a chronic allergic reaction that is triggered by Xl medical in susceptible people.

What are the side effects of Effexor Xl?

Like most psychotropic medications, Effexor Xl has its own gnarly side effects.

You need to address your side effects to your doctor immediately if your side effects are getting too uncomfortable. 

The following are the common side effects of Effexor Xl that was reported by doctors:

  • Lack of appetite
  • Nausea
  • Vomiting
  • Diarrhoea
  • Headache
  • Feeling tired
  • Constipation
  • Heartburn
  • Drowsiness
  • Side effects that emphasize sex such as low arousal or low desire

Allergic reactions/precautions when using Venlafaxine

If you have been experiencing the following side effects, especially allergic reactions of venlafaxine, you need to address this immediately with the doctor:

  • Skin rash or hives
  • difficulty breathing
  • swelling of face, tongue, lips or throat.

In addition, doctors would suggest recording any new or worsening symptoms such as mood or behaviour changes, anxiety, trouble sleeping, panic attacks or if you feel impulsive, irritable, agitated, hostile, restless, aggressive, hyperactive either mentally or physically, more depressed, or have thoughts about suicide or harming yourself.

According to, it is advised to call your doctor at once if you have any of the following: 

  • blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
  • easy bruising or bleeding (nosebleeds, bleeding gums), blood in your urine or stools, coughing up blood;
  • cough, chest tightness, trouble breathing;
  • a seizure (convulsions);
  • low sodium level –headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady; or
  • severe nervous system reaction–very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out.

 What occurs if I miss a dose or have an overdose of venlafaxine?

Missing a dose may trigger withdrawal symptoms and dysphoria.

If you miss a dose attempt to take it as soon as you remember but if it is time to take your next dose then discard the missed dose avoiding a double dose. 

According to an article from Medical News Today, if you take too much of venlafaxine, it can lead to exhibiting some of the following symptoms:

  • Dizziness and puking
  • dilated pupils
  • muscle pain
  • feeling different temperatures
  • drowsiness
  • Dramatic changes in heartbeat
  • seizures
  • coma

Other effects include tremor, vertigo, headache, hallucinations, impaired concentration, fatigue, and paresthesia, which is a sensation of pricking, tingling, or creeping on the skin.

What happens when you withdraw from venlafaxine?

When you withdraw immediately from venlafaxine, you will be experiencing withdrawal symptoms that are apparent from this kind of medication.

This is why you shouldn’t stop taking this kind of antidepressant medication even when you are already treated well. 

The withdrawal symptoms of venlafaxine will be discussed in the following section.

It is important not to get carried away with one’s personal preference to get rid of this antidepressant medication to avoid these kinds of symptoms that may only grant you the risk of harm. 

If the withdrawal symptoms of venlafaxine are growing rapidly, you need to take this kind of antidepressant medication as soon as possible the next day.

You should also try to remember taking this kind of antidepressant medication by setting an alarm when you need to take it. 

There aren’t treatments to minimize the occurrence of withdrawal symptoms from venlafaxine which makes it vital for studies to keep popping up about the credibility of these kinds of symptoms and what needs to be done to treat these symptoms.

In stopping Effexor

Effexor has a half-life cycle in its medical properties which makes it terrifying to immediately stop this antidepressant medication which can cause withdrawal symptoms quickly.

To stop taking this antidepressant medication, doctors would suggest that you gradually schedule the dosage of this antidepressant medication by 37.5 mg to 75 mg per day each week over 4 weeks.

What are the withdrawal symptoms of Effexor as recorded by doctors?

The doctor would suggest and prescribe you take a lower dosage of Effexor before going through the larger dosages.

If you stop taking this antidepressant medication, you will have the misfortune of having withdrawal symptoms from this medication. 

Withdrawal symptoms of Effexor are the following signs:

  • Headaches
  • Nausea
  • Dizziness
  • Unstable moods
  • Gastrointestinal upset
  • Recurrence or relapse of depressive symptoms
  • Bizarre dreams
  • Paresthesias which are unusual sensations of burning, tingling, prickling, etc.

Reviews for Venlafaxine

Here are some reviews from Venlafaxine users taken from and WebMD:

For Anxiety

“Switched to this after Lexapro stopped being effective.

This medication gave me dizziness and nausea-like you wouldn’t believe.

If I didn’t take it exactly on time, I’d start to get withdrawal effects, like brain zaps, which are miserable.

I ate but never felt full. Stopped this and got on Zoloft and felt much better.

Some docs won’t even prescribe this anymore. Beware! GAD, anxiety”

“This medication Effexor was a lifesaver for me. I took Prozac 20 Mg. It worked for a week or 2 and then I had to raise the dosage until I got to 60 mg. My depression was treated but my anxiety was not. I kept having anxiety attacks every now and then. It depends on what form of anxiety u have. Prozac helped with not panicking in stressful situations but did not help with my fear thoughts. With norepinephrine things drastically changed. Though, when I raised from 37.5 to 75 mg my anxiety raised waaaay up. If u want to start at 75 mg make sure u take half and the other half at least after 4 hours until u build up tolerance. Hope it helps u too!!!”

For Depression

“do not take this drug long term…. 20 years down the line when your lymph nodes start to swell you will remember this warning.”

“This stuff is AWFUL. Feels like MDMA but with only the bad effects. Jaw clenching, can’t focus, nausea, shaking. I was literally scared. I called the advice nurse after trying to make myself throw it up because I felt so terrible. Stay AWAY from this drug.”

“I had suffered from dysthymia since I was 14. At the age of 20 I went to seek help for my condition. Been taking different types of SSRI for one year and Due to many side effects, I was put on venlafaxine 150 mg. After a while my life became wonderful. I was flourishing and most of my bad feelings just went away. My self-esteem went up. I felt normal, woke up every morning with good energies. First time for years I was happy.actually happy. That’s been the best days of my life. And then everything deteriorated as I decided to stop. First, I was put on 75 mg, after that 37.5 mg. It was very hard quitting this drug. My dysthymia came back. Been feeling bad for 1 year after I quit, so I decided to take this drug, that changed my life, again. But it didn’t work. I guess I’m thankful for this drug for breaking my illness. This drug actually stopped my dysthymia for a while. After seeing it didn’t work, Been trying different types of SNRI, SSRI, vitamins, b12 supplies but none of them worked. I’m desperate”. 

How do you relieve the withdrawal symptoms of venlafaxine?

As mentioned before, the constant urge to get rid of your antidepressant medication such as venlafaxine is strong.

This is why you should gradually take some of the dosages of this antidepressant medication as prescribed your doctor even if it takes a long time. 

In gradually minimizing the withdrawal symptoms of venlafaxine, the following factors are taken into account:

  • How many periods of time you’ve been taking venlafaxine
  • Your recent dosage where if you’re on a low dosage of venlafaxine, you’ll be able to get off from the effects more immediately
  • Early experience with withdrawal symptoms from venlafaxine or other antidepressant medications
  • Overall health

Even when you are gradually stopping your venlafaxine dosage, there is still the possibility to experience the withdrawal syndrome from this kind of antidepressant medication.

In some recognized cases, the doctor might prescribe you with fluoxetine to minimize your withdrawal symptoms gradually.

Why is this blog about Venlafaxine: A review important?

We have discussed how Venlafaxine can be useful in depression treatment, in addition, it seems to generate fewer side effects than other antidepressant medications.

However, it is important to consider the existing and possible side effects, interactions with any drugs or supplements and some warning signs and precautions before you start a Venlafaxine treatment. 

Also, we have added some reviews from users and their personal experience but remember each person reacts differently to each medication so it tends to vary.

Still, if you start the treatment and don’t see any improvements or side effects only persist and get worse, then it is recommended to contact your doctor either for a dose adjustment or if they see the need to change your medication.  

If you have any questions this review of venlafaxine, please let us know and the team will gladly answer your queries.

Frequently Asked Questions (FAQs) about Venlafaxine: A Review

Does venlafaxine help you focus?

According to WebMD, Venlafaxine helps improve not only your mood but also your concentration.

This newer class of antidepressants is meant to boost the levels of norepinephrine and serotonin in your brain. 

Is venlafaxine a good antidepressant?

Yes, Venlafaxine is considered a good antidepressant, it is also believed to be excellent for the treatment of depression and anxious depression.

How long does venlafaxine take to work?

According to some articles, sleep, appetite or energy may exhibit some improvement within the first 1-2 weeks in afflicted patients.

Enhancement in these physical symptoms can be an important previous signal that venlafaxine is working its effects.

Persistent depressed mood and loss of interest in activities may require up to 6-8 weeks to completely improve.

How does Venlafaxine HCL make you feel?

Venlafaxine can make you feel nauseous, dizzy, sleepy have a dry mouth, constipated, loss of appetite, blurry vision, have trouble sleeping, anxious, unusual sweating, and yawning may occur.

If these symptoms persist or get worse it is recommended to contact your health provider. 

Does venlafaxine give you energy?

Venlafaxine may improve your mood and energy degrees assisting in restoring your interest in regular life activities. It can also decrease anxiety, worry, fear and panic attacks. 


Holliday, S.M and Benfield, P. (1995) Venlafaxine. A review of its pharmacology and therapeutic potential in depression. Venlafaxine Review

Medical News Today


NHS Venlafaxine



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