Paxil vs. Effexor XR: What's the Difference and Which One Should I Take?

Both Paxil and Effexor are effective at treating anxiety and depression, but they are different classes of drugs. Learning how each medication works is the first step toward understanding which one might be best for you. 

This post will explore Paxil and Effexor in detail to help you have an informed discussion with your healthcare provider.

We’ll discuss—

• What are selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs)?
• What mental health conditions does each antidepressant medication treat?
• What are the common forms, doses, and costs of each medication?
• What are the common side effects of each medication?
• Plus, we’ll cover FAQs medical providers on Klarity often receive

Ready to discover how the providers on Klarity can help you? All you have to do is schedule an initial visit and see a board-certified mental health professional within 48 hours. 

This article discusses suicide, suicidal ideation, and self-harm. If you or someone you know is experiencing suicidal thoughts or is in crisis, contact the Suicide Prevention Lifeline immediately at 800-273-8255.

About SSRIs and SNRIs

SSRIs and SNRIs treat anxiety and depression in different ways. Paxil is an SSRI or selective serotonin reuptake inhibitor, and Effexor is an SNRI or selective norepinephrine reuptake inhibitor. Paxil increases the level of serotonin and dopamine in the synapses of the brain, whereas Effexor increases serotonin and norepinephrine. 

Low levels of serotonin and norepinephrine are associated with symptoms of depression and anxiety. Both antidepressants help alleviate symptoms by increasing one or both neurotransmitters, reducing symptoms of depression and anxiety.

To better understand the differences between Paxil and Effexor, it’s important to look at what each neurotransmitter affects. 

What Does Serotonin Do?

Serotonin affects the following bodily functions:

• Mood
• Digestion
• Nausea
• Sleep
• Sexual health
• Wound healing 
• Bone health

What Does Dopamine Do?

Dopamine affects the following bodily functions:

• Pleasurable reward and motivation
• Attention
• Memory
• Behavior and cognition
• Sleep and arousal
• Mood
• Learning
• Lactation
• Movement

What does Norepinephrine Do?

Norepinephrine affects the following bodily functions:

• Fight-or-flight response
• Alertness
• Arousal
• Attention
• Constricts blood vessels
• Mood 
• Memory

Though these neurotransmitters all have a hand in regulating mood, they also affect other systems in the body. This leads to the main side effect differences between Paxil and Effexor, which we’ll address in the following sections.

What Is Paxil?

Paxil (paroxetine hydrochloride) helps increase the amount of available serotonin in the synapses of the brain—the regions where brain cells (called neurons) communicate with one another.

Normally, after the serotonin is used, the neuron reabsorbs it in a process known as “reuptake.” When a person has chronically low serotonin levels, reuptake can deplete what little serotonin is left. SSRIs work by blocking the reuptake channels, keeping serotonin in circulation. Over time, SSRIs can restore serotonin levels in patients.

Paxil Forms and Doses

Paxil comes in capsule, tablet, and liquid form. Additionally, there are controlled-release (Paxil CR) capsules available. Depending on the condition being treated, starting doses of immediate-release Paxil may vary.

Dosages range from 20 mg—a typical starting dose—to 60 mg, which is the maximum dosage. For extended-release Paxil, doses range between 12.5 and 62.5 mg per day.

Paxil is taken once daily with or without food, usually in the mornings. If you experience drowsiness as a side effect, talk to your doctor about possibly taking Paxil in the evening. 

Conditions Paxil Treats

In addition to major depressive disorder (MDD), Paxil is used to treat:

• Generalized anxiety disorder (GAD)
• Post-traumatic stress disorder (PTSD)
• Obsessive-compulsive disorder (OCD)
• Panic disorder
• Postpartum depression
• Social anxiety disorder
• Post-menopausal symptoms

Symptoms of Depression Paxil Can Treat

Paxil can help treat the following symptoms of depression:

• Loss of interest in activities that used to bring joy
• Changes in appetite
• Depressed mood
• Feelings of worthlessness, guilt, hopelessness, and helplessness
• Fatigue
• Trouble concentrating
• Psychomotor agitation—or having nervous energy
• Psychomotor retardation—or feeling trapped in slow motion
• Crying
• Suicidal thoughts or behaviors

Symptoms of Anxiety Paxil Can Treat

Paxil can help reduce the following symptoms of chronic anxiety:

• Excessive anxiety, panic, or feelings of doom
• Irritability
• Restlessness
• Unwanted, compulsive thoughts
• Panic attacks

Paxil Costs

For 30 tablets of 20 mg Paxil, the cost ranges from $4.00 to $30.00. Prices vary due to location, insurance, and pharmacy deals or coupons. Liquid suspensions of Paxil cost more—ranging from $120 to $310.

Paxil Side Effects

Taking Paxil comes with a risk of possible side effects (like any antidepressant). For many, noticeable side effects subside over time. It’s important to remember that your medical provider believes the potential benefits of taking Paxil outweigh any side effects you may experience. Still, it’s crucial to fully understand the risks before taking any antidepressants, including Paxil.

Common Side Effects of Paxil

For many users of Paxil, side effects subside with time. Here are commonly reported side effects of Paxil. Talk with your doctor or medical provider if specific side effects do not go away. 

• Headache
• Nervousness, restlessness
• Drowsiness
• Impotence
• Difficulty having an orgasm
• Dry mouth
• Excessive yawning
• Ringing in the ears
• Dizziness, nausea
• Nasal dryness
• Insomnia
• Constipation
• Weight loss or weight gain
• Decreased sex drive

Paxil Warnings for Use

It’s vitally important to take Paxil as prescribed. Stopping the medication or missing too many doses can lead to the development of withdrawal symptoms, including:

• Irritability
• Nausea
• Feeling dizzy
• Vomiting
• Nightmares
• Headache
• Paresthesias

There is a risk of developing severe side effects when using Paxil and other SSRI antidepressants. Though rare, it’s essential to understand the risks of taking any medication. If you experience severe side effects, contact your psychiatric care provider.

Paxil Black Box Warning 

Using any antidepressant, whether an SSRI or SNRI, comes with the risk of developing suicidal thoughts or thoughts of self-harm. In short-term studies, a small number of patients had suicidal thoughts worsen or developed suicidal thoughts for the first time. You must monitor yourself for increased suicidal thoughts or thoughts of self-harm when taking an SSRI.

If you have thoughts of suicide or of harming yourself, call the Suicide and Crisis Lifeline at 988.

Serotonin Syndrome

There is also a risk of developing a rare condition called serotonin syndrome, which happens when there is too much serotonin in the brain. Certain medications that increase serotonin can lead to this condition, which usually develops within a few hours of ingesting the medication. In rare cases, serotonin syndrome can be fatal.

Be on the lookout for the following symptoms directly after taking any medication that increases serotonin levels:

• Racing heartbeat
• Hallucinations
• Loss of coordination and severe dizziness
• Severe nausea
• Severe vomiting
• Severe diarrhea
• Twitching muscles
• Acute fever

Contact your health provider immediately if you experience any of these severe symptoms.

Paxil Drug Interactions

Paxil may interact with other medications or supplements and cause adverse effects in the body. Paxil, when taken along with other medications, can increase the risk of side effects or cause other conditions. 

Avoid taking monoamine oxidase inhibitors (MAOIs) while taking Paxil. Doctors recommend stopping MAOIs at least two weeks before starting Paxil. Common MAOIs include

• Isocarboxazid
• Linezolid 
• Metaxalone 
• Methylene blue 
• Moclobemide 
• Phenelzine 
• Procarbazine 
• Rasagiline 
• Safinamide 
• Selegiline 
• Tranylcypromine

Taking Paxil alongside blood thinners or other medications that thin the blood can increase the risk of bleeding. Common drugs that thin the blood are:

• Thioridazine
• NSAIDs like ibuprofen
• Warfarin
• Clopidogrel
• Aspirin

Paxil may reduce your body’s ability to metabolize certain drugs, meaning they stay active in your system for longer. Paxil may affect how the following medicines work in your body:

• Atomoxetine 
• Phenothiazines
• Pimozide
• Risperidone
• Tamoxifen
• Tetrabenazine
• Antiarrhythmics
• Desipramine
• Amitriptyline

Tell your doctor about any medications, vitamins, or supplements you are taking before starting Paxil to avoid adverse drug interactions.

What Is Effexor?

Effexor (venlafaxine hydrochloride) is an SNRI, a class of antidepressants that block the reuptake of both serotonin and norepinephrine in the brain’s synapses. Unlike Paxil, which increases serotonin, Effexor works on an additional neurotransmitter—norepinephrine. 

Because Effexor works on both serotonin and norepinephrine, it has different effects on the brain than Paxil. As a result, specific side effects and treatment options vary. People who don’t respond well to treatment with Paxil might respond better to Effexor because it affects a different chemical channel in the brain.

Effexor Forms and Doses

Effexor comes in capsules and tablets with immediate-release and extended-release (XR) options. For immediate-release pills, the standard dose is 150 mg per day, but Effexor also comes in 17mg, 25 mg, 37.5 mg, and 100 mg doses. Effexor XR capsules come in a standard dose of 75 mg, but 37.5 and 150 mg XR capsules are available.

Make sure you use the medication as prescribed. Usually, patients are directed to take Effexor once a day at the same time each day, with or without food.

Conditions Effexor XR Treats

Effexor is FDA-approved to treat various mental health conditions and disorders including major depressive disorder, panic disorder, social anxiety disorder, and generalized anxiety disorder. Additionally, it is used off-label to treat other conditions. 

Symptoms of Anxiety Effexor Can Treat

Effexor has been shown to reduce certain symptoms of anxiety:

• Excessive anxiety
• Catastrophizing
• Panic
• Feelings of doom
• Fatigue
• Sleep disturbances
• Irritability
• Muscle tension
• Difficulty concentrating
• Restlessness

Symptoms of Depression Effexor Can Treat

Prescribed use of Effexor has also been shown to reduce symptoms of depression as well, including

• Chronically depressed mood
• Frequent crying
• Loss of interest in hobbies and activities
• Psychomotor agitation—or having nervous energy
• Psychomotor retardation—or feeling trapped in slow motion
• Sudden weight loss or weight gain
• Suicidal thoughts or behaviors
• Feelings of worthlessness, guilt, hopelessness, and helplessness
• Fatigue
• Trouble concentrating

Off-Label Uses for Effexor

Psychiatric care providers sometimes prescribe Effexor as an off-label treatment for other related mental health conditions, including

• Post-traumatic stress disorder (PTSD)
• Obsessive-compulsive disorder (OCD)
• Diabetic neuropathy
• Hot flashes
• Migraine prevention
• Complex pain syndromes
• Premenstrual dysphoric disorder (PMDD)
• Attention deficit hyperactivity disorder (ADHD)
• Fibromyalgia

Effexor XR Costs

150 mg of generic Effexor, called venlafaxine, generally ranges between $13 and $48 dollars. However, the cost depends on several factors, including the region you are purchasing the medication, your access to health insurance, and which pharmacy you use. 

Effexor XR Side Effects

Like SSRIs, SNRIs come with the risk of side effects. It’s important you discuss these with your psychiatric healthcare provider before starting treatment. Medical professionals prescribe Effexor when they determine that the benefits of the medication outweigh any potential risks. 

Effexor’s most common side effects appear in the first few weeks of treatment. Usually, they decrease or disappear entirely after a few months. Talk with your doctor if certain side effects persist and interfere with your daily life. 

Common side effects include:

• Headache, dizziness, drowsiness, tiredness
• Anxiety, nervousness, restlessness
• Sleep disturbances 
• Strange dreams
• Changes in weight or appetite
• Dry mouth, increased yawning
• Increased sweating
• Sexual dysfunction
• Tremors
• Heart racing
• Blurred vision
• Nausea and vomiting 
• Diarrhea or constipation

There is a risk of experiencing more severe side effects, which Effexor users need to be aware of:

• Seizures
• Blurred vision/seeing halos around lights
• Difficulty breathing/chest tightness
• Abnormal bleeding
• Unnaturally stiff muscles
• Low blood sodium—confusion, headaches, and memory problems

If you experience severe side effects, contact your health care provider immediately.

Effexor XR Warnings for Use

If your symptoms improve or you don’t notice any effects while taking Effexor, it’s vitally important that you still use the medication as prescribed. If you and your medical provider decide Effexor isn’t right for you, you need to gradually wean off the drug to prevent the risk of developing withdrawal symptoms, which include:

• Anxiety and depression
• Feeling dizzy
• Nightmares
• Paresthesias
• Nausea
• Headaches 
• Irritability 
• Vomiting

Effexor might not be the right medication for people with certain preexisting medical conditions:

• Hypertension
• Interstitial lung disease
• Glaucoma
• Hyponatremia, or SIADH
• Seizure disorder
• Liver disease
• Kidney disease
• Bipolar disorder

Like with SSRIs, SNRIs increase the levels of serotonin in the brain, which can lead to a severe but rare condition called serotonin syndrome. This condition usually develops within the first few hours of taking medication that elevates serotonin levels. Monitor for symptoms if you are using Effexor and are already taking medication that affects serotonin levels. 

If you’re experiencing severe side effects from taking Effexor, contact your healthcare provider as soon as possible.

Effexor Black Box Warning 

As with Paxil and many other SSRIs and SNRIs, there is a chance that Effexor users will experience an increase in suicidal thoughts. This is more common in teens and younger adults, however, it can still occur in older adults. 

It’s important that Effexor users monitor themselves for increased thoughts of self-harm and suicide. Also, ask others to monitor you for unusual changes in behavior, such as acting withdrawn or more depressed.

If you have thoughts of suicide or self-harm, immediately contact the Suicide and Crisis Lifeline at 988.

Effexor XR Drug Interactions

People who have previously used MAOIs or monoamine oxidase inhibitors must wait at least two weeks after stopping that medication before starting Effexor, as there is a risk of severe drug interactions. Common MAOIs include:

• Marplan (isocarboxazid)
• Azilect (rasagiline)
• Nardil (phenelzine)
• Emsam (selegiline)
• Parnate (tranylcypromine)

Effexor increases the risk of bleeding. Patients on blood thinners or other drugs that thin the blood as a side effect need to monitor for an increased risk of bleeding. Common medications that thin the blood are:

• Advil
• Motrin
• Coumadin
• Aspirin

What Antidepression Medication Should I Take?

Paxil and Effexor are both approved by the FDA to treat symptoms of anxiety, major depressive disorder, and related mental health disorders. However, your body chemistry may respond differently to SSRIs and SNRIs.

This fact, when taken into consideration with your medical history, means that one might work better for you than the other. Or, there may be a better third option for treating your anxiety and/or major depressive disorder. It’s crucial to talk with your healthcare provider about which medication is best for you.

If you aren’t happy with your current antidepressant medication, consider switching over to a different medication that has less severe or fewer side effects. Always consult with your doctor before stopping or switching medication.

Frequently Asked Questions about Paxil and Effexor XR

Here are some common questions Klarity receives about Paxil and Effexor:

Can I drive on Paxil or Effexor XR?

When first starting Paxil or Effexor, it’s important to monitor for any side effects like dizziness, nausea, confusion, or tiredness, which might impact your ability to drive. If you do not experience these symptoms, or if they go away in the first couple of weeks, then you are clear to drive while taking Paxil or Effexor. 

Discuss possible side effects of Paxil or Effexor with your doctor and how they may impact your daily life.

Can Paxil or Effexor make anxiety worse?

Potentially. Both SSRIs and SNRIs can make anxiety symptoms worse depending on the patient. If you experience worsening anxiety symptoms, talk to your medical provider right away. Remember, it’s important to take Paxil or Effexor as directed. 

Stopping abruptly can make symptoms worse.  Your psychiatric healthcare provider can develop a plan to wean you off the medication if indicated.

Does Paxil or Effexor XR affect pregnancy?

Generally, Paxil and Effexor are considered safe to take while pregnant. However, be sure to discuss your pregnancy with your medical provider, who will decide which medication is safest for you to take.

What’s better for depression? Paxil or Effexor?

Both Paxil and Effexor are equally effective at treating chronic depression and its symptoms.

Can I drink alcohol while using Paxil or Effexor XR?

It is not recommended that patients drink any amount of alcohol while using Paxil or Effexor. The presence of alcohol can increase the risk of experiencing adverse side effects and can make the effects of alcohol stronger. In addition, alcohol is a depressant that can increase some symptoms of depression.

Does it matter what time of day I take Paxil or Effexor XR?

Generally, it doesn’t matter which time of day you take Effexor or Paxil; however, doctors recommend you take it at the same time every day. If you experience side effects like drowsiness or sleepiness, then it may be best to take the medication at night. 

Your healthcare provider will determine which time of day you should take your medication.

What’s better for anxiety? Paxil or Effexor?

Paxil is FDA-approved to treat more anxiety-related conditions than Effexor, but Effexor is often prescribed “off-label” for many of the same conditions. Both can be effective in treating symptoms of anxiety. Your psychiatric healthcare provider will determine the best medication for you based on your medical history and anxiety symptoms.

Get Depression and Anxiety Treatment Today From a Healthcare Provider on Klarity

Klarity has already helped 30,000 people connect with depression and anxiety-trained mental health specialists and get online treatment for their anxiety or depression. If you are weighing the pros and cons of SSRIs vs SNRIs, a board-certified medical provider on Klarity can help you figure out which medication treatment, if any, is right for you.

Schedule an appointment and discover how Klarity can help you. 

Sources

“Dopamine.” Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22581-dopamine

“Effexor XR.” drugs.com. https://www.drugs.com/paxil.html

John Cunha. “Paxil vs. Effexor.” RxList. https://www.rxlist.com/paxil_vs_effexor/drugs-condition.htm

“Norepinephrine (Noradrenaline).” Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22610-norepinephrine-noradrenaline

“Paxil.” Drugs.com. https://www.drugs.com/paxil.html

“Serotonin.” Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22572-serotonin