Paxil (Paroxetine) - Oral

Paxil pills spilling out of bottle
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Paxil (paroxetine) is a type of antidepressant known as a selective serotonin reuptake inhibitor or SSRI. It is used in the treatment of several mental health disorders related to anxiety and depression.

If you have been prescribed Paxil, it's important to know its potential side effects, precautions, dosage, and more. Here we share all of this information, including ways to stay healthy while taking this drug.

The Most Important Things to Know About Paxil (Paroxetine)

  • Some people experience serious side effects with Paxil, such as seizures or suicidal thoughts, requiring immediate medical attention.
  • It is possible to overdose on Paxil and this drug can also interact with other substances—including over-the-counter medicines and alcohol.
  • Talk to your healthcare provider before taking Paxil if you are pregnant or breastfeeding or have liver disease.

What Is Paxil?

Paroxetine, the generic form of Paxil, was first introduced in 1992 and quickly became popular for treating major depression and anxiety disorders. As an SSRI, it blocks the reabsorption of the neurotransmitter serotonin. This increases the levels of serotonin in the brain, which helps regulate mood.

Paxil has been approved by the U.S. Food and Drug Administration (FDA) for the treatment of:

Paxil is also sometimes prescribed off-label for the treatment of irritable bowel syndrome. "Off-label" means that the drug has not been FDA-approved for this particular condition.

How to Take Paxil

Paxil is usually taken once daily and may be taken with or without food. It is important to take this medication as directed by your physician and never take it in higher amounts or more often than prescribed. 

Tablets should be swallowed whole and not be broken, crushed, or chewed. If you are taking the liquid oral suspension, always shake the bottle well before measuring your dose. Only use a spoon or oral syringe that contains the accurate amount.

Storage

Paxil should be kept in a closed container at room temperature. The medication should also be kept away from direct light, moisture, heat, and freezing temperatures. Always store Paxil out of the reach of children and dispose of any outdated medication.

Side Effects of Paxil

Like other medications, there is a risk of experiencing side effects when taking Paxil. These effects may be noticed when first taking the drug. They may also be side effects of increasing the Paxil dosage.

Common Side Effects

Some of the most common side effects associated with Paxil use include:

  • Dizziness
  • Dry mouth
  • Headache
  • Loss of appetite
  • Mental fogginess
  • Nervousness and jitters
  • Sexual issues
  • Sleepiness and yawning
  • Upset stomach and nausea
  • Weight gain

After your body begins to adjust to the medication, side effects such as these may reduce. If you experience adverse effects that remain persistent or are bothersome, consult with your healthcare provider. Your provider may reduce your dosage or switch medicines to provide some relief.

Severe Side Effects

Some Paxil side effects happen less frequently but are more serious. They include:

  • Abnormal bleeding
  • Allergic reaction, including symptoms such as swelling of the face, lips, or tongue, or difficulty swallowing
  • Chest pain
  • Confusion
  • Fainting
  • Fast or irregular heartbeat
  • Hallucinations
  • Numbness in the extremities
  • Seizures
  • Skin that peels or blisters
  • Suicidal thoughts

Call your physician immediately or seek emergency medical attention if you experience any of these serious side effects after taking Paxil.

Any SSRI antidepressant also has a risk of producing a potentially life-threatening condition called serotonin syndrome. This rare condition is usually the result of an interaction of two or more drugs that affect brain serotonin levels. Even some over-the-counter supplements, such as St. John’s Wort, can result in serotonin syndrome if mixed with SSRIs.

A particularly troublesome interaction is mixing SSRIs with a class of antidepressants called monoamine oxidase inhibitors (MAOIs), which should not be taken with SSRIs. It is recommended that Paxil is avoided for two weeks before or after using an MAOI.

FDA Black Box Warning

As of 2004, the FDA has required that all antidepressants carry a black box warning. This warning is designed to let users know that the drug may increase suicidal thoughts and behaviors, especially in children, adolescents, and young adults.

If you or a loved one has been prescribed an antidepressant such as Paxil, continuous monitoring is important. Any changes in behavior or worsening depression should be immediately reported to the prescribing physician—especially if they occur when first starting the drug or after a change in dosage.

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 988 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

Long-Term Side Effects

There are no known problems connected to the long-term use of paroxetine. The medication is considered safe when used as prescribed and directed.

Dosage of Paxil

Paxil tablets are available in doses containing 10 mg, 20 mg, 30 mg, and 40 mg of paroxetine. It is also available in a liquid oral solution with each 5 mL of liquid containing 10 mg of paroxetine.

Your care provider may begin therapy with a low dose that can be increased if your symptoms do not improve. Starting at a low dose can also minimize some side effects because it gives your body time to adjust to the medication.

Paxil CR is a controlled-release formula that works by taking a single dose that processes in the body throughout the day. This formulation of Paxil is offered in 12.5 mg, 25 mg, and 37.5 mg tablets.

All listed dosages are according to the drug manufacturer. Check your prescription and talk to your physician to make sure you are taking the right dose for you.

Missed Dose

If you miss a dose of your antidepressant, take it as soon as you remember, unless it’s nearly time to take your next dose. Do not take extra Paxil to make up for the missed dose.

Overdose of Paxil

Taking too much medication may result in an overdose. Symptoms of a Paxil overdose can include:

  • Abnormally excited mood
  • Aggressive behavior
  • Drowsiness
  • Fast or irregular heartbeat
  • Fever or sweating
  • Nausea or vomiting
  • Seizures
  • Urine that is dark red or brown in color

Call your doctor or emergency medical services if you think a Paxil overdose has occurred. You can also call poison control at 1-800-222-1222.

Precautions for Paxil

Paxil is not right for everyone and people with certain medical conditions or concerns should not take Paxil. If you are taking Paxil, here are some things you should consider.

What Are Reasons I Should Not Take Paxil?

Keep in mind that this list is not all-inclusive. There can be other medical issues your doctor may need to consider.

  • Pregnancy: Studies have linked Paxil to an increased risk of birth defects, particularly heart defects, when taken during the first trimester of pregnancy. Some of these defects are mild and resolve without intervention, but some may be quite serious. Other research has found that exposure to SSRIs during pregnancy may increase the risk of persistent pulmonary hypertension, a serious lung disorder, in a newborn.
  • Breastfeeding: If you are nursing or are pregnant, it is best to discuss the risks and benefits of SSRI therapy with your obstetrician.
  • NSAIDs or Aspirin: Use of Paxil with NSAIDs may be associated with an increased risk of bleeding.
  • Liver Disease: Before taking Paxil, tell your physician if you have impaired liver function. Depending on your condition, your physician may adjust your dose and perform certain tests while on Paxil therapy to help minimize side effects.
  • Alcohol: Drinking alcohol while taking Paxil is not recommended.

Drug Interactions With Paxil

Paxil may interact with other medications, including monoamine oxidase inhibitors (MAOIs). Paxil should not be taken with or within two weeks of taking MAOIs. 

Other medications that may interact with Paxil include:

  • Strattera (atomoxetine)
  • Abilify (aripiprazole)
  • Risperdal (risperidone) 
  • Coumadin (warfarin)
  • Tricyclic antidepressants
  • Cardiac medications
  • Medications containing ibuprofen or aspirin

Tell your healthcare provider about all medications you are taking before beginning paroxetine, including over-the-counter drugs and dietary supplements.

Medications Similar to Paxil

There are other SSRIs that can help boost serotonin levels in the brain. If Paxil does not work for you, talk to your physician about trying one of the following alternatives:

  • Prozac (fluoxetine)
  • Celexa (citalopram)
  • Zoloft (sertraline)
  • Lexapro (escitalopram)

How to Stay Healthy While Taking Paxil

It may take some time for Paxil to begin working, so talk to your provider about what you can do to manage your symptoms in the meantime. They may recommend talking to a mental health professional and utilizing psychotherapy alongside your medication.

Certain self-care strategies may also be beneficial. They include getting adequate sleep, engaging in regular physical activity, and reaching out for support from friends and loved ones.

It's important to take Paxil exactly how it is prescribed. If you have questions or concerns, talk with your healthcare provider.

Discontinuing Paxil Use

Before discontinuing Paxil, talk with your care team. Some people have reported withdrawal symptoms when decreasing or stopping paroxetine. It is believed that these symptoms are the result of the brain trying to stabilize serotonin levels after an abrupt change.

Symptoms that may occur during the discontinuation of antidepressants include:

  • Increased anxiety or feelings of panic
  • Irritability
  • Suicidality

When discontinuing Paxil your healthcare provider may gradually reduce your dosage to help avoid or reduce these withdrawal symptoms.

Frequently Asked Questions

  • How long does Paxil last?

    It takes four to 14 days for Paxil to reach steady levels in the body, and the effects will last as long as you continue to take the medication. Once you stop taking Paxil, it may remain active in your system for several days after your last dose.

  • How long does Paxil stay in your system?

    The elimination half-life of Paxil is approximately 21 hours. The half-life refers to how long it takes for half a dose to be metabolized and eliminated by the body. It can take around five days for Paxil to be eliminated from your system.

  • How long does it take for Paxil to work?

    Some people experience some improvement in symptoms within one or two weeks of starting paroxetine. The full therapeutic effect, however, may not be achieved for several weeks.

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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Sheryl Ankrom, MS, LCPC
Sheryl Ankrom is a clinical professional counselor and nationally certified clinical mental health counselor specializing in anxiety disorders.