Paxil (Paroxetine) Facts

• Generic name: Paroxetine hydrochloride
• Brand/Trade names: Paxil, Paxtine
• Dosages:
  Tablets 10 mg, 20 mg, 30 mg, 40 mg;
  Suspension, oral 10 mg per 5 mL
  Tablets, controlled-release 12.5 mg, 25 mg, 37.5 mg
• Pharmacologic category: Selective serotonin reuptake inhibitor
• FDA approved: December 29, 1992
• Manufacturer: GlaxoSmithKline
• Habit forming? No
• Pregnancy risk factor: D

Paxil (Paroxetine hydrochloride) is an agent in a newer class of antidepressant medication known as selective serotonin reuptake inhibitors (SSRIs).
This antidepressant medication has been approved by the U.S. Food and Drug Administration as a safe and effective treatment for these conditions:

• Depression
• Generalized Anxiety Disorder (GAD)
• Social Anxiety Disorder
• Panic Disorder
• Obsessive Compulsive Disorder (OCD)
• Posttraumatic Stress Disorder (PTSD)

With continued treatment, Paxil can help restore the balance of serotonin (a naturally occurring chemical in the brain) - which helps reduce the symptoms of anxiety and depression.

When will Paxil start to work?

It is considered that if you don't feel any positive benefit after four to six weeks, then you should talk to your doctor about trying another medication.
Generally, if Paxil is going to work for you, you will notice some improvement in 1-2 weeks.

• Absorption: Completely absorbed via oral administration. Food does not reduce its absorption.
• Metabolism: Paroxetine undergoes extensive first-pass metabolism in the liver. At least 85% of a paroxetine is oxidized to a catechol intermediate that undergoes subsequent methylation and conjugation to clinically inactive glucuronide and sulfate metabolites. Metabolism is accomplished in part by cytochrome P450 2D6 (CYP2D6) ; saturation of this enzyme at clinical doses appears to account for the nonlinear kinetics observed with increasing dose and duration of paroxetine treatment. The elderly may be more susceptible to the saturation of hepatic metabolic capacity, leading to conversion to nonlinear kinetics, which results in increased plasma concentrations of paroxetine at lower-than-usual doses .
• Elimination half-life: 24 hours
• Excretion: Urinary excretion of unchanged paroxetine is generally less than 2% of dose whilst that of metabolites is about 64% of dose. About 36% of the dose is excreted in faeces, probably via the bile, of which unchanged paroxetine represents less than 1% of the dose. Thus paroxetine is eliminated almost entirely by metabolism.

• very potent SSRI
• FDA approved for use in all five anxiety disorders
• effective for depression of all types including mild, moderate and severe depression, and including depression comorbid with anxiety and physical illnesses
• effective in preventing relapse or recurrence of depression in patients treated for up to 1 year

• severe discontinuation syndrome and high rate of of withdrawal reactions [1]
• highest rate of sexual side effects [2]
• potential for weight gain higher than with other SSRIs [4]
• more sedating and constipating than other SSRIs
• potential for drug interactions

• premature ejaculation
• chronic headache [3]
• bipolar disorder
• irritable bowel syndrome (IBS) [8]
• pathological gambling [7]
• fibromyalgia
• hot flashes [5]
• diabetic neuropathy [6]

Paroxetine is a potent and highly selective inhibitor of neuronal serotonin reuptake. Paroxetine inhibits the reuptake of serotonin at the neuronal membrane, enhances serotonergic neurotransmission by reducing turnover of the neurotransmitter, therefore it prolongs its activity at synaptic receptor sites and potentiates 5-HT in the CNS. Paroxetine is more potent than both sertraline and fluoxetine in its ability to inhibit 5-HT reuptake. Paroxetine very weakly inhibits reuptake of norepinephrine and dopamine.

• Paxil (Paroxetine) reviews and ratings (recommended medication by 54% of reviewers): http://psychcentral.com/meds/paxil.html
• Paxil (Paroxetine) discussion: http://www.paxilprogress.org/forums/
• Paxil, Paxil CR, Paroxetine forum: http://www.topix.net/forum/drug/paxil
• Paxil (Paroxetine) successes and progress, good stories and bad: http://www.paxilprogress.org/forums/forumdisplay.php?s=c8e2dee0f765dbd14ceaee3328daa5bb&f=7
• Paroxetine message board: http://paroxetine.suddenlaunch2.com/
• Paxil, Seroxat, Deroxat, Paroxetine discussion: http://www.depressionforums.org/forums/index.php?showforum=57
• Paxil (Paroxetine) withdrawal:
• Paxil discontinuationn recipe on MedicalNewsToday.com
• Withdrawal techniques on PaxilProgress.org
• Withdrawal discussion on PaxilProgress.org
• Paxil Withdrawal on MedHelp.org
• Paxil Withdrawal on DepressionForums.org
• Paxil (Paroxetine) side effects:
• Sex and Paxil: http://www.depressionforums.org/forums/index.php?showtopic=1912
• What is the worst side effect you have suffered with this medication? http://www.depressionforums.org/forums/index.php?showtopic=5768
• Paxil (Paroxetine) and Pregnancy
• Anyone taken paroxetine whilst pregnant on EssentialBaby.com.au

• 1. Stahl MM, Lindquist M, Pettersson M, Edwards IR, Sanderson JH, Taylor NF, Fletcher AP, Schou JS. Withdrawal reactions with selective serotonin re-uptake inhibitors as reported to the WHO system. Eur J Clin Pharmacol. 1997;53(3-4):163-9. PubMed
• 2. Montejo-Gonzalez AL, Llorca G, Izquierdo JA, Ledesma A, Bousono M, Calcedo A, Carrasco JL, Ciudad J, Daniel E, De la Gandara J, Derecho J, Franco M, Gomez MJ, Macias JA, Martin T, Perez V, Sanchez JM, Sanchez S, Vicens E. SSRI-induced sexual dysfunction: fluoxetine, paroxetine, sertraline, and fluvoxamine in a prospective, multicenter, and descriptive clinical study of 344 patients. J Sex Marital Ther. 1997 Fall;23(3):176-94. PubMed
• 3. Foster CA, Bafaloukos J. Paroxetine in the treatment of chronic daily headache. Headache. 1994 Nov-Dec;34(10):587-9. PubMed
• 4. Fava M. Weight gain and antidepressants. J Clin Psychiatry. 2000;61 Suppl 11:37-41. PubMed
• 5. Stearns V, Beebe KL, Iyengar M, Dube E. Paroxetine controlled release in the treatment of menopausal hot flashes: a randomized controlled trial. JAMA. 2003 Jun 4;289(21):2827-34. PubMed
• 6. Sindrup SH, Grodum E, Gram LF, Beck-Nielsen H. Concentration-response relationship in paroxetine treatment of diabetic neuropathy symptoms: a patient-blinded dose-escalation study. Ther Drug Monit. 1991 Sep;13(5):408-14. PubMed
• 7. Kim SW, Grant JE, Adson DE, Shin YC, Zaninelli R. A double-blind placebo-controlled study of the efficacy and safety of paroxetine in the treatment of pathological gambling. J Clin Psychiatry. 2002 Jun;63(6):501-7. PubMed
• 8. Tabas G, Beaves M, Wang J, Friday P, Mardini H, Arnold G. Paroxetine to treat irritable bowel syndrome not responding to high-fiber diet: a double-blind, placebo-controlled trial. Am J Gastroenterol. 2004 May;99(5):914-20. PubMed