Paxil Information, Dosage, and Side Effects

Paxil pills spilling out of bottle
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Paxil (paroxetine) is an SSRI antidepressant introduced in 1992 by GlaxoSmithKline. Paxil was the first formally approved SSRI for the treatment of panic disorder in the United States. Paxil is available in a generic equivalent, paroxetine, and is indicated for the treatment of:

Dosage Information

Paxil, and its generic equivalent, paroxetine, are manufactured in scored tablets of 10, 20, 30, and 40 mg. It is also available in a liquid oral solution. Your doctor may begin therapy with a low dose that may be increased if your symptoms do not improve.

Starting at a low dose can also minimize some of these side effects because it gives your body time to adjust to the medication. Paxil (paroxetine) is usually taken once each day and may be taken with or without food.

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

Other Important Details

You should take Paxil exactly how it is prescribed. If you have questions or concerns, talk with your doctor. In the meantime, here are some of the most commonly asked question about Paxil.

  • How long does it take 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.
  • Is Paxil Addictive? Paxil is not believed to be addictive or habit-forming.
  • What if I miss a dose? If you miss a dose, 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 the missed dose.

Side Effects

Some of the common side effects associated with Paxil therapy include:

  • Weakness
  • Drowsiness
  • Dizziness
  • Nausea
  • Anxiety or nervousness
  • Dry mouth
  • Insomnia
  • Constipation or diarrhea
  • Increased sweating
  • Decreased libido, erectile dysfunction, ejaculatory/orgasmic inability or delay.

Some people experience a reduction in some of these side effects after being on the medication for a while. If they remain bothersome, though, you should consult with your doctor.

When to Call a Doctor

If you experience any of the following less common side effects, you should call your doctor right away:

  • Agitation or irritability
  • Restlessness
  • Impulsiveness
  • Hyperactivity
  • Tremors

You should get emergency medical attention if you experience any of the following rare, but serious, side effects:

  • Allergic reaction—difficulty breathing; swelling of your face, lips or tongue or difficulty swallowing.
  • Seizures
  • Confusion
  • Hallucinations
  • Fainting
  • Suicidal thoughts

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 1-800-273-8255 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

These are not the only side effects that may be experienced with paroxetine. You should report any bothersome side effects to your doctor or other healthcare professional.

Precautions and Contraindications

Be sure to tell your doctor about all medications, including over-the-counter drugs and supplements, you are taking before beginning paroxetine. If you are taking Paxil, here are some things you should consider.

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

  • Pregnancy: Recent 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. It has also been suggested that exposure to SSRIs during late 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 doctor.
  • NSAIDs or Aspirin: Use of Paxil with NSAIDs or aspirin may be associated with an increased risk of bleeding.
  • Liver Disease: Before taking Paxil, tell your doctor if you have impaired liver function. Depending on your condition, your doctor may need to adjust your dose and perform certain tests while on Paxil therapy.
  • Alcohol: Drinking alcohol with Paxil should generally be avoided.

Serotonin Syndrome

Any SSRI antidepressant 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.

SSRI Discontinuation Syndrome

Before discontinuing Paxil, talk with your doctor. Some people have reported withdrawal-like symptoms when decreasing or stopping SSRI therapy. 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 discontinuation of any SSRI therapy include:

  • Nausea
  • Headache
  • Muscle Aches
  • Dizziness
  • Electric shock-like sensations in the neck and head

While all of these symptoms are not believed to be dangerous, they can be quite upsetting. When discontinuing an SSRI, your doctor may give you a gradual reduction schedule to avoid these withdrawal-like symptoms.

FDA Black Box Warning

The association of increased suicidal thoughts, especially among adolescents with SSRI treatment, has been a center of attention and controversy in recent years. In response to the concerns suggested in case studies and some research, the U.S. Food and Drug Administration (FDA) issued a statement in 2007.

The FDA proposed that makers of all antidepressant medications indicate a warning on their products about a possible increased risk of suicidal thinking and behavior in children, adolescents, and young adults.

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7 Sources
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