Psychiatry Pharm

Antidepressant

Bupropion

• Type:
  • 1st line antidepressant
    
• Note:
  • NOT associated with sexual side effects or weight gain
    
• Side effects:
  • increased seizure risk @ high doses
    
• C/I:
  • seizure disorder patient, anorexia nervosa and bulimia

Trazodone

• Type:
  • Antidepressant
    
• Clinical Use:
  • Also treats depression-related insomnia
    
• Side effect:
  • sexual dysfunction, priapism

Anti-epileptic

• function to reduce GABA catabolism:
  • Valproic acid
    
  • Vigabatrin

1st generation antihistamine

Cyproheptadine

• Type:
  • 1st generation antihistamine with nonspecific 5-HT1 and 5-HT2 receptor antagonist properties
    
• Clinical Use:
  
  • An antidote to serotonin syndrome

1st gen antipsychotic

• MOA:
  • D2 receptor ANTAGONIST
    
  • Lowers the seizure threshold
• Clinical Use:
  • treat schizophrenia
• Low potency:
  • chlorpromazine, thioridazine
    
• Side effects:
  • anticholinergic, sedation (histaminergic blockade), orthostatic hypotension (alpha-1 adrenergic block)
    
• High potency:
  • haloperidol, fluphenazine
    
• Side effects:
  • extrapyramidal (acute dystonia, parkinsonism, akathisia)

Chlorpromazine

• MOA:
  • Low potency 1st generation antipsychotics (FGA), mostly anticholinergic side effects

Haloperidol

• MOA:
  • 1st generation antipsychotic (high potency), D2 antagonist so mostly neuro side effects

2nd gen antipsychotic

• MOA:
  • D2 receptor antagonist + serotonin type 2 receptor antagonist (stop too much of a good thing)

Clozapine

• Type:
  • 2nd generation antipsychotic
    
• Clinical Use:
  • Refractory treatment for schizophrenia
• Side effect:
  • neutropenia (< 1000) and agranulocytosis (regularly monitor neutrophils)

Quetiapine

• Type:
  • 2nd generation antipsychotic
    
• MOA:
  • D2 receptor antagonist AND serotonin 2A antagonist (all 2nd gens)
• Clinical Use:
  • Can treat bipolar disorder
    
• Risk:
  • Lower risk for dystonic side effects in comparison to 1st generation antipsychotics

Risperidone

• Types:
  • 2nd gen antipsychotic
    
• Side effect:
  • weight gain, hyperprolactinemia (galactorrhea, amenorrhea)

Bipolar medications

Lithium

• MOA:
  • Acts vis inositol monophosphatase
• Clinical Use:
  • Treats bipolar disorder
    
• Side effects:
  • hypothyroidism, renal function (nephrogenic diabetes insipidus, chronic tubulointerstitial nephropathy) so check TSH, BUN, and creatinine regularly
    
• Toxicity:
  
  • Acute toxicity –> vomiting, diarrhea, delirium
    
    • Begins with N/V, diarrhea –> neuromuscular signs develop later
  • Chronic lithium toxicity –> gradual onset of neurologic symptoms –> ataxia/tremor
    
• In pregnant patients:
  • associated with Ebstein anomaly (abnormal tricuspid valve)
• Notes:
  • Narrow therapeutic index
    
• Interactions:
  • Filtered/reabsorbed mostly by proximal tubules (acts like sodium) SO any decreased GFR will cause an increased sodium/lithium reabsorption
    
  • Thiazide diuretics can potentiate lithium toxicity because of volume depletion in distal tubule –> stimulates proximal tubule to step up reabsorption
    
  • ACE inhibitors, and NSAIDs also –> impaired lithium clearance/toxicity
• Lithium induced hypothyroidism:
  • Presentation:
    • Weight gain, hair loss, mild bradycardia
      
    • Look for goiter
      
  • Treatment:
    
    • levothyroxine (T4) supplement, don’t discontinue the lithium

Anticonvulsants

• Types:
  • Carbamazepine
  • Lamotrigine
  • Phenytoin
• Clinical Use:
  • Used to stabilize mood during bipolar disorder as well
    
• Side effects:
  • carbamazepine — aplastic anemia.
  • lamotrigine — rash, Stevens-Johnson syndrome

Antihistamine

Diphenhydramine

• Type:
  • Antihistamine
    
• Avoid in the elderly:
  • due to anticholinergic effects and increased risk of sedation/delirium

Anxiolytic

Buspirone

• Type:
  • nonbenzodiazepine anxiolytic
• Clinical Use:
  • used to treat generalized anxiety disorder. Partial agonist of 5HT1A receptor.
    
• Notes:
  • Slow onset of action
    
  • No muscle relaxant/anticonvulsant properties. Does NOT treat panic disorders.
    
  • No risk of dependence

Baclofen

• MOA:
  • GABA B agonist
    
• Clinical Use:
  • Treats spastic conditions, less effective on alcohol withdrawal

GABA receptor agonism

• Types:
  • Ethanol
    
  • Barbiturates
    
  • Benzos
    
  • Propofol

Barbiturates

• MOA:
  • Act @ separate allosteric site — prolong the duration of channel openings in response to GABA
    
  • @ higher doses: GABA-A receptor antagonists

Phenobarbital

• MOA:
  • Anticonvulsant that enhances GABA activity

Benzodiazepines

• MOA:
  • Work at the GABA-A receptor complex
    
  • Allosterically modulate the binding of GABA –> increased FREQUENCY of chloride ion channel opening –> neuronal hyperpolarization and inhibited action potential
• Clinical Use:
  • CNS depressant
    
  • Substitute for alcohol on GABA A receptors to enhance inhibitory action of GABA –> prevent alcohol withdrawal

Alprazolam

• Type:
  • XANAX (Benzodiazepine)
    
• Clinical Use:
  
  • Treats anxiety/panic disorders

Clonazepam

• Brand name:
  • Klonopin
• Type:
  • Anticonvulsant/antiepileptic
• Clinical Use:
  • Treats panic attacks

Diazepam

• Brand name:
  • Valium
• Type:
  • Benzodiazepine
    
• Clinical Use:
  • Treats alcohol withdrawal, anxiety and seizures
    
• Risk:
  • If stop medication can have withdrawal symptoms

Flurazepam

• Type:
  • -Long-Acting
• Clinical Use:
  • It can treat difficulty sleeping (insomnia), hypnotics, long-acting
    
  • -Sleep inducing
    
  • -Sleep maintenance, increase the duration of sleep
    
  • -decrease number of awakening
    
  • -Very little rebound insomnia
    
• Risk:
  • Day time drowsiness, liver disorder

Lorazepam

• Name brand:
  • Ativan
• Type:
  • Anxiolytics
• Clinical Use:
  • treat seizure disorders, such as epilepsy.
  • used before surgery and medical procedures to relieve anxiety.
    

Temazepam

• Type:
  • -intermediate-acting
• Clinical Use:
  • 1-2 to have effect; oral, intermediate, good for frequent awakening, hypnotics

Triazolam

• Type:
  • hypnotics, short-acting
    
  • Short half-life
• Clinical Use:
  • for a patient with recurring insomnia
    
  • Insomnia is a sleep disorder that is characterized by difficulty falling and/or staying asleep.

Propofol

• Clinical Use:
  • general anesthetic

Hypertensives

• Short-acting:
  • esmolol, nitroprusside (good to treat HTN associated with serotonin syndrome)
    
• Long half life:
  • propranolol (avoid for serotonin syndrome b/c could develop hypotension/shock)

Hypnotic

Zolpidem

• Type:
  • Hypnotic
• Clinical Use:
  • used for insomnia

MAOI

• Monoamine oxidase:
  • An enzyme located in PREsynaptic nerve terminals that is responsible for the breakdown of monoamine neurotransmitters
• MAOI Types:
  • phenelzine
  • selegiline
  • tranylcypromine
    
• MOA:
  • Irreversibly binds/inhibits MAO: A and B –> increased neurotransmitter release into the synaptic cleft
• Monoamine (serotonin) receptors:
  • G protein-coupled receptors
• Monoamine reuptake inhibitors:
  • TCAs and SSRIs
    
  • Usually, presynaptic neurons actively take up norepinephrine, dopamine and serotonin through reuptake transporters –> repackage into synaptic vesicles for future neurotransmission

Linezolid

• Type: 
  • MAOI

Phenelzine

• Type:
  • MAOI

Prazosin

• MOA:
  • alpha-1 adrenergic blocker
    
• Clinical Use:
  • Treats HTN and urinary retention due to BPH
    
• Adverse effect:
  • hypotension (postural especially)

Psychostimulants

• Types:
  • 1st line: non-amphetamines (modafinil)
    
  • 2nd line: amphetamines (due to sympathomimetic side effects)
• Clinical Use:
  • Narcolepsy treatment
• Treatment
  
  •  
• MOA:
  • Low levels of hypocretin-1 which is a neurotransmitter involved in maintaining wakefulness and suppressing REM sleep-related phenomena (hallucinations, paralysis)
    
• C/I:
  • zolpidem or benzos

SNRI

Venlafaxine

• Type:
  • SNRI
    
• Associated:
  • w/ increased BP especially @ higher doses, sexual dysfunction

SSRI

• Precursor for serotonin:
  • Tryptophan

Citalopram

• MOA:
  • SSRI
    
• Side effect:
  • sexual dysfunction

Paroxetine

• Type:
  • SSRI
    
• Clinical Use:
  
  • Treats depression, OCD, PTSD, anxiety

Sertraline

• Brand Name: 
  • Zoloft
• MOA:
  • SSRI –> serotonin syndrome (agitated delirium, autonomic instability, seizures, myoclonus, hyperreflexia, diaphoresis)

Tricyclic antidepressants

• MOA:
  • Amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, doxepin, amoxapine
    
  • STRONG ANTICHOLINERGIC EFFECTS! (amitriptyline especially)
• Anticholinergic effects:
  • Fever, delirium, mucosal/axillary dryness, cutaneous flushing, non-reactive mydriasis, urinary retention, ANHIDROSIS, tachycardia
    
  • TCAs can cause this! –> confusion, constipation, urinary retention (ex: amitriptyline) –> C/I in elderly because comorbidities increase side effects

Drug combinations

• Cocktail:
  • 10mg Haldol, 25-50mg Benadryl, 4mg Ativan
• Dr. Pepper:
  • 10mg Haldol, 2mg Cogentin, 4mg Ativan

Meds to avoid in geriatric patients

• Avoid to treat insomnia:
  • Benzodiazepines
    
  • Antihistamines
    
  • Sedating antidepressants
    
  • Antipsychotics
    
  • Treatment:
    • ramelteon (melatonin agonist)

Similar MOA

• Enhancing GABA inhibitory action:
  • Alcohol, barbiturates, and benzodiazepines

Medication induced syndrome

Neuroleptic malignant syndrome

• Presentation:
  • Rigidity (lead pipe), sympathetic overdrive, mental status changes
    
• Caused by:
  • antipsychotics (neuroleptics) 1-3 days after initiation/dose increase
    
• Treatment:
  • stop the neuroleptic. Severe cases treated w/benzos and dantrolene (postsynaptic muscle relaxant)

Serotonin syndrome

• Path:
  • When an MAOI is combined w/SSRI, SNRI, or TCA –> produce excessive synaptic serotonin levels due to decreased reuptake AND decreased serotonin degradation
• Presentation:
  • Hyperthermia, confusion, myoclonus, cardiovascular instability, diaphoresis, flushing, diarrhea, seizures.
  • 1. autonomic instability
  • 2. altered mental status
  • 3. neuromuscular hyperactivity
• Treatment:
  • 2-week washout period after discontinuing an MAOI before initiating an SSRI to allow enough time for MAO generation
  • OR cyproheptadine (antihistamine that functions as a serotonin antagonist when given as antidote)

Antidote for Overdose

Withdrawal

Alcohol withdrawal

• Presentation:
  • Tremors, agitation, insomnia, autonomic hyperactivity (elevated pulse/blood pressure) within 48 hrs following admission
    
  • Delirium begins 2-4 days after alcohol withdrawal
    
• Treatment:
  • Benzodiazepines (lorazepam, diazepam, chlordiazepoxide)

Benzo withdrawal

• Presentation:
  • Anxiety, tremor, insomnia, palpitations, diaphoresis
    
  • Severe: psychosis and seizures
    
• Greatest risk:
  • short-acting agents (alprazolam), prolonged use, high doses

Opioid withdrawal

• Presentation:
  • N/V, diarrhea, lacrimation, dilated pupils, piloerection

SSRI withdrawal

• Presentation:
  • Rebound anxiety/dysphoria, dizziness, headache, nausea