Paroxetine

Paroxetine is used to treat depression, panic attacks, anxiety disorders, and a severe form of premenstrual syndrome (premenstrual dysphoric disorder). It works by helping to restore the balance of a certain natural substance (serotonin) in the brain.

Paroxetine is known as a selective serotonin reuptake inhibitor (SSRI). This medication may improve your mood, sleep, appetite, and energy level and may help restore your interest in daily living. It may decrease fear, anxiety, unwanted thoughts, and the number of panic attacks. Paroxetine may lessen premenstrual symptoms such as irritability, increased appetite, and depression.

Paroxetine may also be used to treat other mental/mood disorders (such as obsessive-compulsive disorder-OCD, post-traumatic stress disorder). It may also be used to treat hot flashes that occur with menopause.

Paroxetine is available under the following different brand names: Paxil, Brisdelle, Paxil CR, and Pexeva.

Dosages of Paroxetine:

Adult Dosage Forms and Strengths

Tablet

• 10 mg
• 20 mg
• 30 mg
• 40 mg

Capsule

• 7.5 mg

Tablet, extended-release

• 12.5 mg
• 25 mg
• 37.5 mg

Oral suspension

• 10 mg/5mL

Dosage Considerations – Should be Given as Follows:

Depression

• Conventional: 20 mg orally once/day initially; may increase by 10 mg/day once weekly not to exceed 50 mg/day
• Paxil CR: 25 mg orally once/day initially; may increase by 12.5 mg/day once weekly not to exceed 62.5 mg/day

Obsessive-Compulsive Disorder

• 20 mg orally once/day initially; may increase by 10 mg once weekly, not to exceed 60 mg/day

Panic Disorder

• 10 mg orally once/day initially; may increase by 10 mg once weekly (target dose 40 mg/day), not to exceed 60 mg/day, OR
• Paxil CR: 12.5 mg orally once/day initial, increase by 12.5 mg once weekly not to exceed 75 mg/day

Social Phobia

• 20 mg orally once/day OR
• Paxil CR: 12.5 mg orally once/day initially; may increase by 12.5 mg once weekly, not to exceed 37.5 mg/day

Generalized Anxiety Disorder

• 20 mg orally once/day initially, may increase by 10 mg once weekly, up to 50 mg/day doses have been used but no increase in benefit seen at doses greater than 20 mg/day

Posttraumatic Stress Disorder

• 20 mg orally once/day initially; may increase by 10 mg once weekly, up to 50 mg/day doses have been used but no increase in benefit seen at doses greater than 20 mg/day

Premenstrual Dysphoric Disorder

• Paxil CR: 12.5 mg orally once/day initially; may increase at 1-week intervals not to exceed 25 mg/day

Menopausal Vasomotor Symptoms

• Brisdelle: Indicated to treat moderate-to-severe vasomotor symptoms associated with menopause
• Brisdelle: 7.5 mg orally at bedtime
• Paxil CR (Off-label): 12.5-25 mg orally once/day

Dosing Considerations

• Pediatric: Safety and efficacy not established
• Geriatric: Caution should be used in the elderly because paroxetine is the most sedating and anticholinergic of the selective serotonin reuptake inhibitors
• The elderly are prone to SSRI/SNRI-induced hyponatremia; monitor closely

Common side effects of paroxetine include:

• Nausea
• Insomnia
• Dry mouth
• Headache
• Weakness or lack of energy
• Constipation
• Diarrhea
• Dizziness
• Ejaculation disorder
• Tremor
• Anxiety
• Blurred vision
• Decreased appetite
• Impotence
• Nervousness
• Numbness and tingling
• Mania (mild)

Other side effects of paroxetine include (based on 40 mg dose):

• High blood pressure (hypertension)
• Fast heart rate
• Mood swings
• Itching
• Weight gain
• Joint pain
• Ringing in the ears
• Spinning sensation (vertigo)
• Angle-closure glaucoma

Serious side effects of paroxetine include:

• Worsening depression
• Mania (rare)
• Serotonin syndrome
• Suicidal thoughts (rare)
• Suicide (rare)
• Seizure (rare)
• Toxic epidermal necrolysis
• Hyponatremia (rare)
• Abnormal bleeding (rare)
• Acute hepatitis (rare)
• Stevens-Johnson Syndrome

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

Severe Interactions of paroxetine include:

• eliglustat
• isocarboxazid
• phenelzine
• pimozide
• procarbazine
• selegiline
• thioridazine
• tranylcypromine

Paroxetine has serious interactions with at least 96 different drugs.

Paroxetine has moderate interactions with at least 175 different drugs.

Paroxetine has mild interactions with at least 40 different drugs.

This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information about this medicine.

Warnings

• In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (younger than 24 years) taking antidepressants for major depressive disorders and other psychiatric illnesses.
• This increase was not seen in patients aged older than 24 years; a slight decrease in suicidal thinking was seen in adults older than 65 years.
• In children and young adults, risks must be weighed against the benefits of taking antidepressants.
• Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during the initial 1-2 months of therapy and dosage adjustments.
• The patient's family should communicate any abrupt changes in behavior to the healthcare provider.
• Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy.
• This drug is not approved for use in pediatric patients.
• This medication contains paroxetine. Do not take Paxil, Brisdelle, Paxil CR, or Pexeva if you are allergic to paroxetine or any ingredients contained in this drug.
• Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.

Contraindications

• Hypersensitivity
• Concomitant pimozide
• Co-administration with serotonergic drugs
  • Concomitant use or within 14 days of MAOIs increases the risk of serotonin syndrome
  • Reactions to concomitant administration with MAOIs include tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome, seizures, rigidity, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma
  • Starting paroxetine in a patient who is being treated with linezolid or IV methylene blue is contraindicated because of an increased risk of serotonin syndrome
  • If linezolid or IV methylene blue must be administered, discontinue SSRI immediately and monitor for CNS toxicity; may resume 24 hours after last linezolid or methylene blue dose, or after 2 weeks of monitoring (5 weeks for fluoxetine), whichever comes first

Effects of Drug Abuse

• None

Short-Term Effects

• See "What Are Side Effects Associated with Using Paroxetine?"

Long-Term Effects

• See "What Are Side Effects Associated with Using Paroxetine?"

Cautions

• Clinical worsening and suicidal ideation may occur despite medication in adolescents and young adults (18-24 years)
• Use caution in patients with bipolar disorder, seizure disorder, history of suicidal thought/behavior
• Life-threatening serotonin syndrome reported with SNRIs and SSRIs alone; also with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, amphetamines, and St.John's wort)
• Risk of mydriasis; may trigger angle closure attack in patients with angle-closure glaucoma with anatomically narrow angles without a patent iridectomy
• Conflicting evidence regarding the use of SSRIs during pregnancy and increased risk of persistent pulmonary hypertension of the newborn
• Risk of complications such as feeding difficulties, irritability, and respiratory problems reported in neonates exposed to SNRIs/SSRIs late in the third trimester
• Risk of cardiovascular defects in infants whose mothers took drugs during early pregnancy
• Withdraw gradually
• Use lower starting dose in renal impairment (CrCl less than 30 mL/min) or severe hepatic impairment
• Increases risk of hyponatremia and impairment of cognitive and motor functions in the elderly
• May cause or exacerbate sexual dysfunction
• Inability to remain still due to feelings of agitation or restlessness reported; may occur within the first few weeks of therapy
• May impair platelet aggregation especially when used in combination with aspirin or NSAIDs; increases risk of bleeding in patients taking anticoagulants/antiplatelets concomitantly
• Epidemiologic studies on bone fracture risk following exposure to some antidepressants, including SSRIs, have reported an association between antidepressant treatment and fractures; there are multiple possible causes for this observation and it is unknown to what extent fracture risk is directly attributable to SSRI treatment
• Bone fractures reported being associated with antidepressant use
• Consider the risk of serotonin syndrome if administered concomitantly with other serotonergic drugs including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, amphetamines, and St.John's wort

Pregnancy and Lactation

• Only use paroxetine during pregnancy in LIFE-THREATENING emergencies when no safer drug is available. There is positive evidence of human fetal risk
• Teratogenic effects: Epidemiologic studies have shown that infants exposed to paroxetine in the first trimester of pregnancy have an increased risk of congenital malformations, particularly cardiovascular malformations
• Use of paroxetine late in the third trimester is associated with complications in newborns and may require prolonged hospitalization, respiratory support, and tube feeding
• A study of nearly 28,000 women taking SSRIs confirmed 5 previously reported birth defects associated with paroxetine, including heart defects, anencephaly, and abdominal wall defects (BMJ 2015; 351:h3190)
• Persistent pulmonary hypertension of the newborn:
  • The potential risk of persistent pulmonary hypertension of the newborn (PPHN) when used during pregnancy
  • Initial public health advisory in 2006 was based on a single published study; since then, there have been conflicting findings from new studies, making it unclear whether the use of SSRIs during pregnancy can cause PPHN
  • FDA has reviewed the additional new study results and has concluded that, given the conflicting results from different studies, it is premature to reach any conclusion about a possible link between SSRI use in pregnancy and PPHN
  • FDA recommendation: FDA advises health care professionals not to alter their current clinical practice of treating depression during pregnancy and to report any adverse events to the FDA MedWatch program
  • A meta-analysis of 7 observational studies, found exposure to SSRIs in late pregnancy (i.e., greater than 20 weeks gestation) more than doubled the risk of PPHN that could not be explained by other etiologies (e.g., congenital malformations, meconium aspiration) (BMJ 2014;348:f6932)
  • Paroxetine is excreted in breast milk; use caution if breastfeeding (the American Association of Pediatrics [AAP] states the effect on nursing infants is unknown but may be of concern)