Antidepressants and Depression Diagnosis

• Antidepressants are a widely prescribed drug class with well-understood neurotransmitter profiles
• The mnemonic "SIG E CAPS" helps recall depression symptoms: Sleep changes, Interest loss, Guilt, Energy decrease, Concentration difficulties, Appetite changes, Psychomotor slowing or agitation, and Suicidal thoughts

Diagnosing depression

• Having at least five "SIG E CAPS" symptoms qualifies as major depressive disorder per DSM standards
• Symptoms must occur for two weeks, remembered with the mnemonic "2 Blue Weeks"

Serotonin Specific Reuptake Inhibitors (SSRIs)

• SSRIs inhibit serotonin transporters on presynaptic neurons
• This increases serotonin availability in the synaptic cleft

Serotonin functions

• The mnemonic "Head, Red, and Fed" summarizes serotonin functions
• Head: Psychological effects like satisfaction and decreased impulsivity, but also decreased sex drive (a common reason for stopping SSRIs)
• Red: Effects on platelets, potentially causing prolonged bleeding
• Fed: GI effects are prominent side effects and another common reason for stopping the medication

SSRI efficacy

• Maximum treatment efficacy often takes 4-6 weeks
• Side effects like diarrhea or restlessness are immediate, while desired effects take longer

Fluoxetine (Prozac)

• Fluoxetine was the first immediately successful SSRI
• Has a long half-life due to its metabolite norfluoxetine
• Benefits those who struggle with medication adherence
• Requires caution when switching to other serotonergic drugs to avoid serotonin syndrome
• The "flu" in fluoxetine can remind you that is lasts about a week

Sertraline (Zoloft)

• The "ser" in sertraline is a reminder for "serotonin"
• Pronouncing it "Zertraline" helps pair it with the brand name Zoloft
• Known for harsher GI side effects like nausea and diarrhea (nickname "Squirt-raline")
• Taking sertraline with food can improve absorption and decrease GI side effects
• Considered one of the safer SSRIs for pregnant or breastfeeding women

Paroxetine (Paxil)

• Rapidly absorbed, leading to quicker side effects at the start and faster withdrawal symptoms
• The "pair ox" in paroxetine can remind you that it moves faster than a single ox
• Rapid absorption can cause withdrawal symptoms in patients and newborns
• Use caution in pregnant patients due to potential newborn seizures

Citalopram (Celexa)

• Considered a middle-of-the-road SSRI
• It is generally considered by some psychiatrists to be an excellent first-line agent due to its overall high tolerability
• Fairly clean in terms of enzyme interactions
• Concern about QTc interval prolongation at higher doses (>40mg/day for adults, >20mg/day for elderly)
• Yearly EKGs are recommended at higher doses
• Renaming it "Alexis" can remind you to get an electrocardiogram (EKG), picture Alexis electric car

Escitalopram (Lexapro)

• The awesome younger sibling of Celexa
• An S-enantiomer of citalopram, which is the pharmacologically active form
• A 10mg dose is equivalent to a 20mg dose of citalopram
• Even cleaner than citalopram regarding enzyme interactions

Fluvoxamine (Luvox)

• An older antidepressant primarily approved for obsessive-compulsive disorder (OCD) in the U.S.
• Pronouncing it "luv-OC" or "fluvox-OC" can help associate it with OCD
• Other SSRIs can also help with OCD
• Fluvoxamine is unique because it is FDA approved for OCD rather than depression

Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

• Serotonin regulates satisfaction and anxiety, while norepinephrine increases energy and focus

Venlafaxine (Effexor)

• A reuptake inhibitor for both serotonin and norepinephrine
• The "venlafaxINE" can remind you of norepinephrine
• Might be preferred over SSRIs if primary symptoms are lack of energy, decreased interest, and impaired concentration
• Can cause hypertension due to norepinephrine effects on the peripheral vascular system

Duloxetine (Cymbalta)

• The "dual" in duloxetine reminds you of dual mechanisms
• Often used for chronic pain as it mitigates pain sensation
• Can remember this by thinking duh L'Occitane in addition to duloxetine Dolph or dulls the pain

Mirtazapine (Remeron)

• A different mechanism of action increases appetite, which helps guard against cachexia
• The mnemonic "meal-tazapine" can remind you that it makes you want to eat a meal
• Also tends to decrease nausea

Bupropion (Wellbutrin)

• Works primarily through dopamine and norepinephrine
• The "bu-" can be associated with "butane" which can help link to "D&N" (dopamine and norepinephrine)
• Does not have significant sexual side effects
• Indicated to help patients stop smoking
• Because its an "upper" has a propensity to lower the seizure threshold
• Strongly contraindicated for treating depression in bulimic patients

Trazodone (Desyrel)

• Used as an antidepressant and a sleeping aid, especially in depressed patients
• A serotonin antagonist and reuptake inhibitor
• Can cause priapism, an erection lasting several hours, which is a medical emergency
• The mnemonic "trouser-done" can help you remember this side effect

Tricyclic Antidepressants (TCAs)

• Inhibit the reuptake of serotonin and norepinephrine
• Antagonize acetylcholine and histamine
• Inhibit sodium and calcium ion channels
• Very effective antidepressants but have significant side effects

Tricyclic Antidepressants Pros and Cons

• Serotonin and norepinephrine are primarily responsible for antidepressant action
• Reserved for treatment-resistant depression
• Acetylcholine inhibition causes antimuscarinic side effects: dry mouth, blurry vision, constipation, urinary retention, memory impairment, and increased body temperature
• Histamine antagonism results in sedation and sleepiness
• Sodium and calcium channel inhibition can cause mood stabilization effects
• Overdoses can cause significant heart and nerve conduction abnormalities

Tricyclic Antidepressants Overdose

• A widened QRS complex in the context of a suspected overdose is pathognomonic for TCA overdose
• Treatment for TCA overdose is sodium bicarbonate
• Rhyme Trans Chans and Ans: TCAs act as an agonist at two neurotransmitters, an antagonist at another two, and an inhibitor of two different ion channels

Avoiding Serotonin Syndrome

• A washout period of two weeks is needed when switching from an SSRI to a tricyclic
• Fluoxetine requires a five-week washout period due to its long half-life

Imipramine

• The first tricyclic antidepressant ever developed
• Sometimes used for managing nocturnal enuresis (bedwetting) in children
• Anticholinergic effect prevents bladder contraction
• Pronouncing it "I'm-peeing-ramine" can remind you of bedwetting

Clomipramine

• Only FDA-approved for the treatment of OCD
• Gold standard for medication treatment of OCD
• Reserved for more severe refractory cases due to the high side effect profile

Amitriptyline and Nortriptyline

• Prototypical TCAs also prescribed for chronic pain issues

Monoamine Oxidase Inhibitors (MAOIs)

• Modulate serotonin, norepinephrine, and dopamine
• Among the most effective antidepressants, especially for atypical depression
• Have severe side effects due to multiple interactions
• Seen as a last resort

Hypertensive crisis

• Eating tyramine-containing foods (aged wine and cheeses) while on an MAOI can lead to a hypertensive crisis
• "Being on Maui (MAOI), on a date with Miss Tyra (tyramine) Banks, enjoying fine wines and cheese" can help to remember this interaction

Selegiline and Phenelzine

• Two MAOIs to remember
• Both are irreversible inhibitors
• Selegiline is selective for MAO-B
• Phenelzine is non-selective, hitting both MAO-A and MAO-B

MAO-A and MAO-B

• MAO-A degrades serotonin, norepinephrine, dopamine, and tyramine
• MAO-B degrades only dopamine
• Phenelzine (hits both MAO-A and MAO-B) is preferable for depression
• Selegiline (hits only MAO-B) is preferable for Parkinson's

When to Refer to a Psychiatrist "PSYCH MD"

• Psychosis
• Suicidality
• Why isn't this working? (multiple failed treatment attempts)
• Comorbid psychiatric disorders (including substance abuse)
• Highs and lows of bipolar disorder
• Monitoring drugs (such as lithium)