Flashcards in Antidepressant Pharmacology Deck (70)
1. First line treatment for depressive disorders?
2. Efficacy between the SSRIs?
3. Differences in what? 2
1. First line treatment of depressive disorders
2. No real differences in efficacy
3. Difference in side effects and half lives
SSRIs in the order of development
1. Fluoxetine (Prozac) 1987
2. Sertraline (Zoloft)
3. Paroxetine (Paxil)
4. Citalopram (Celexa)
5. Fluvoxamine (Luvox)
6. Escitalopram (Lexapro) 2002
SSRIs are used to treat various psychiatric conditions
2. Panic disorder
3. Obsessive-compulsive disorder
4. Generalized anxiety disorder
5. Social anxiety disorder
6. Post traumatic stress disorder
7. Body dysmorphic disorder
8. Bulimia nervosa
9. Binge eating disorder
10. Premenstrual dysphoric disorder
11. Somatoform disorders
SSRIs block what?
reabsorption of serotionin
1. Block the presynaptic serotonin reuptake pump
2. Increases the time that serotonin is available in the synapse
3. Increases postsynaptic receptor occupancy
1. Well absorbed where?
2. Reach peak plasma levels when?
3. Metabolism and elimination occur where?
4. Metabolites are inactive except for _________ has an active metabolite
1. Well absorbed in the GI tract
2. Reach peak plasma levels in 1-8 hours
SSRIs downstream effects
1. Increased production of neuroprotective proteins such as what?
2. Down-regulation of 5HT1A receptors (5HT1A receptors when bound with serotonin inhibits the neuron from releasing serotonin) so less inhibition = what?
1. brain-derived neurotrophic factor
2. more firing and increased serotonin release in the presynaptic neuron
SSRI half life:
1. Half life range is what?
2. Except for what?
1. In general elimination half life range is 20-30 hours
2. Except for fluoxetine (Prozac) half life is up to 3 days and it’s active metabolite can last 4-16 days
Fluvoxamine’s (Luvox) half life is about what?
Which SSRIs inhibit liver enzymes less than other SSRI’s? 2
Citalopram and escitalopram
2D6, 2C9, 2C19, 2B6, 3A4, 1A2
-Different ones in each SSRI
-Citalopram and escitalopram don’t seem to be affected by these
SSRIs: Drug interactions. Use with caution with what drugs?
Contraindicated if taking ______ within 2 weeks due to risk of serotonin syndrome
Paroxetine and fluoxetine are contraindicated with what?
1. Azole antifungals
2. Macrolide antibiotics
4. Hepatic impairment
tamoxifen used to treat breast cancer
SSRI Side effects
Sexual dysfunction (17%)
Weight gain (12%)
Rash or pruritis
Withdrawal syndrome if abrupt discontinuation
More common in which SSRIs? 2
3. GI distress
More common with fluvoxamine and paroxetine (shorter half lives)
SSRI response time?
1. Some will feel better in a few weeks
2. Others 4-6 weeks
1. Dosing how often?
2. Take when? 2
1. Usually once daily dosing
-If it makes them sleepy have them take it at night
-If is causes insomnia have them take it in the AM
3. Warn of common side effects like HA, dizziness, nausea, diarrhea when first starting so they know that these side effects are expected
SSRI Duration of therapy:
1. For many it is lifelong
2. Don’t stop it for 1 year after the resolution of symptoms
3. Stopping the medication too early may cause recurrence of a severe depressive episode
Citalopram (Celexa) 20-40mg: Good to use when?
concerned about drug interactions (doesn’t have the P450 enzyme inhibition as strong as the other SSRIs)
Citalopram (Celexa) 20-40mg: Risk of what at doses over 40mg or those at high risk for arrhythmia?
What pts are at high risk for arrhythmia while taking celexa?
1. Hepatic impairement
2. Age > 60 years
3. On other CYP219 inhibitors (cimetidine)
Escitalopram (Lexapro) 10-20mg
1. Its an isomer of what?
1. Isomer of citalopram
2. Similar to citalopram as has fewer drug interactions then others in the class
Fluoxetine (Prozac) 20-40mg daily
1. Contraindicated with what?
2. More likely to cause what than others?
3. Least likely to cause what?
1. Contraindicated with Tamoxifen
2. More likely to cause activation than the others
3. Least problems with weight gain
Fluvoxamine (Luvox) 50-200mg daily
1. Dosing schedule?
2. Weight gain?
3. More likely to have which SE compared to other SSRIs? 2
1. Twice daily dosing if at 200mg daily
2. Weight gain up to 2.6% of body weight
3. More likely to have nausea and sedation compared to most other SSRIs
Paroxetine (Paxil) 20-40mg daily
1. Contraindicated with who?
2. Common SE? 2
3. Withdrawl symptoms?
4. Weight gain?
1. Contraindicated with Tamoxifen
2. Nausea and sedation more likely to occur than most others
3. Significant withdrawal symptoms
4. Causes the most weight gain among the SSRIs (up to 3.6% of baseline)
Sertraline (Zoloft) 50-200mg daily
-More likely tot cause what than others?
More likely to cause diarrhea than the others
1. What is a big risk as the pt starts feeling better?
2. Possible increases in what other things? 2
3. Can affect what in males?
1. May increase the risk of suicide as the patient recovers (risk greatest in ages 18-24)
-May increase the risk of abnormal bleeding
-Possible increase in bone fractures
3. May affect male fertility
Abnormal levels of DNA fragmentation in sperm were noted compared to baseline 50% vs 10%
What are the SNRIs? 3
1. Venlafaxine (Effexor)
2. Duloxetine (Cymbalta)
3. Desvenlafaxine (Pristiq)
SNRIs act on which neurotransmitters? 2
When would we use these?
Act on both serotonin and norepinephrine
Can use for treatment of depression if intolerable side effects or poor response to first line SSRI therapy
Other uses for SNRIs
Generalized anxiety disorder
Social anxiety disorder
Body dysmorphic disorder
Diabetic peripheral neuropathy
Menopausal hot flashes
1. Food decreased what but not what in absorption?
2. Which ones do not significantly inhibit P450 enzymes? 2
3. Which one does?
1. Food decreases the rate of absorption but not the degree of absorption
2. Desvenlafaxine and venlafaxine do not significantly inhibit P450 enzymes
3. Duloxetine moderately inhibits P450 enzymes so will have more drug interactions