Pharm Flashcards
Levodopa (L-DOPA) (Dopar)
- class: dopamine precursor
- crosses BBB→DA; improves nigrostriatal functioning
- +carbidopa= first-line treatment for Parkinson’s (unless patient is young; delay use as long as possible)
- side effects: dyskinesias; hypotension, nausea, anxiety, fatigue; psychoses if dosed too high
- MAO-A inhibitors contraindicated (MAO-Bonly hits DA)
Carbidopa (Lodosyn)
- class: aromatic AA decarboxylase inhibitor
- inhibits peripheral conversion of L-DOPA to dopamine; does not cross BBB
- given with Levadopa to lower side effects
- treats parkinson’s
- side effects: dyskinesias, on-off phenomenon
- MAO-A inhibitors contraindicated (MAO-B only hits DA)
Buproprion (Wellbutrin)
- class: norepi-dopamine reuptake inhibitor (NDRI)
- blocks DAT→ increased DA synthesis
- treats: parkinson’s, SAD, good for patients with addictive behavior (maintain nicotine abstinence in quitting smokers);
- side effects due to increased NE: insomnia, anxiety, agitation, nausea, dry mouth, sweating, palpitations; mild increase in BP
- less pronounced DA side effects because it’s less aggressive in CNS and not 100% agonist
- lowers seizure threshold
Modafinil
Armodafinil
- class: stimulants
- increases histamine activity in tuberomammilary nucleus; may block DAT
- wake promoting; treats narcolepsy, apnea
- side effects: similar to but less severe than amphetamines; less addictive than the phetamines
Selegiline (Eldepryl)
Rasagiline (Azilect)
- class: MAO-B inhibitor (more relevant for DA)
- prevents breakdown of DA
- treats: early Parkinson’s
- side effects: hypotension (due to NE→ a1), dizziness, insomnia, weight gain; N/V
- selegiline: patch for depression too (EMSAM)
Tranylcypromine (Parnate)
Isocarboxazid (Marplan)
Phenelzine (Nardil)
- class: MAOI
- irreversibly inhibits MAO-A and MAO-B
- treats depression
- side effects: hypotension, dizziness, insomnia, weight gain
- HTN crisis with tyramine rich foods
- serotonin syndrome (MAOI + SSRI)
Entacapone (Comtan)
Tolcapone (Tasmar)
- class: COMT inhibitor
- prevents breakdown of DA
- treats parkinson’s (good add on for other drugs)
- side effects: nausea, fatigue; dopamine side effects
- entacapone: short acting (2 hours)
- tolcapone: use only if entacapone fails, risk of liver failure
Bromocriptine (Parlodel)
Pramipexole (Mirapex)
Ropinerole (Requip)
Apomorphine (Apokyn)
- class: D2 receptor agonist
- increases DA activity (phasic)
- treats: mild/early parkinson’s, restless leg syndrome
- side effects: mania, nausea, dizziness, fatigue; peripheral DA-like effects
- less effective with motor symptoms of PD
- bromocriptine: treats hyperprolactinemia; must be titrated slowly due to hypotension
Aripiprazole (Abilify)
- class: D2 & D3 receptor (partial) agonist
- increases DA activity (tonic)
- treats: schizophrenia; depression
- side effects: less side effects than other DA
Amantadine (Symmetrel)
- class: antiviral
- ? stimulates D2 receptors, blocks DAT; leads to DA release from terminal vesicles
- treats: mild parkinson’s (2nd-line; not used much); influenza
- side effects: nausea, dizziness, psychosis, insomnia, seizures
- contraindicated in elderly with dementia (anticholinergic effects)
Reserpine
Tetrabenazine
- class: synapse depleter
- blocks VMAT (no release of monoamines into synapses)
- reserpine: treats HTN
- tetrabenazine: treats huntington’s
- side effects: depression (lowers NA and DA)
Benztropine (Cogentin)
Trihexiphenidyl (Artane)
Diphenhydramine
- benztropine, trihexiphenidyl: anticholinergics; contraindicated in parkinson’s dementia; abrupt discontinuation exacerbates symptoms
- diphenhydramine: antihistamine
- muscarinic receptor antagonist (inhibiting cholinergic tone in basal ganglia improves DA tone in nigrostriatal pathway)
- treats: early parkinson’s, reduces EPS
- side effects: dry mouth, blurred vision, racing heart, constipation, confusion, delirium, hallucinations
First-generation antipsychotics (Low Potency)
- Chlorpromazine, thioridazine
- non-selective D2 receptor antagonism (also H1, anticholinergic, and a1 antagonism)
- treats psychosis (schizophrenia)
- side effects: EPS; fatigue and weight gain (H1 antagonism); anticholinergic effects; orthostasis (alpha1 antagonism)
- tardive dyskinesia with chronic use
- little effect on negative symptoms
First-generation antipsychotics (High Potency)
- Fluphenazine, thiothixine, haloperidol
- non-selective D2 receptor antagonism
- treats: psychosis (schizophrenia); movement disorder in Huntingtons
- side effects: EPS; NMS (skeletal muscles microcontract→hyperthermia, muscle rigidity)
- tardive dyskinesia with chronic use
- little effect on negative symptoms
Second-Generation Antipsychotic (Low potency)
- ‘pines: olanzapine, quetiapine, asenapine
- D2 receptor antagonist, 5HT2a receptor antagonist
- less EPS but more sedating
- treats: psychosis, mania, agression
- side effects: suicide risk in ages <25; metabolic syndrome; TD/EPS; stroke in dementia patients
Clozapine (Clozaril)
- class: second generation antipsychotic (low potency)
- D2 (& D1, D4) receptor antagonist; 5HT2a receptor antagonist
- treats refractory shizophrenia (use if all else fails)
- side effects: similar to other “pines”; agranulocytosis, most metabolic risk of all antipsychotics, but little EPS/TD; must monitor WBC
Second-Generation Antipsychotics (High Potency)
- ‘dones: risperidone, ziprazidone, paliperidone, iloperidone, lurasidone
- D2 receptor antagonist; but various other receptor agonism/antagonism
- higher potency, more EPS
- treats: psychosis, mania, agression
- side effects: suicide risk in ages <25; metabolic syndrome; TD/EPS; stroke in dementia patient, fewer metabolic complications than ‘pines
Pilocarpine HCl (Salagen)
- class: direct muscarinic agonist
- pupillary constriction, increased aqueous outflow
- treats: glaucoma (open angle and acute closed angle); cataract surgery
- used infrequently due to side effects (decreased vision when patient has cataracts due to miosis, headache; SLUDGE)
AChEI
- Edrophonium: short-acting, fast onset; used to diagnose myasthenia gravis
- Echothiophate: irreversible, long acting; treats glaucoma
- Neostigmine: MC used for reversal of NMB; more complete antagonism than edrophonium
- Pyridostigmine: Longer acting than neostigmine, edrophonium
- side effects: SLUDGE
Atropine
Scopolamine
- class: antimuscarinic
- pupillary dilatation; paralysis of ciliary body
- treats: improve discomfort during active eye inflammation (ueveitis)
- side effects: ataxia, nystagmus, restlessness, mental confusion, hallucination, violent and aggressive behavior, insomnia, photophobia, urinary retention
- atropine: v. long acting so not used unless inflammation is severe
Tropicamide (Mydriacyl)
- class: antimuscarinic
- pupillary dilatation; paralysis of ciliary body
- treats: MC used cycloplegia for eye exams
- side effects: ataxia, nystagmus, restlessness, mental confusion, hallucination, violent and aggressive behavior, insomnia, photophobia, urinary retention
Epinephrine (Epinal)
- class: direct adrenergic agonist
- dilation of episcleral vessels→ increased aqueous outflow and a1 pupillary dilation
- side effects: extrasystoles, palpitation, hypertension, myocardial infarction, trembling, paleness, sweating
Hydroxyamphetamine (Paredrine)
- class: indirect adrenergic agonist
- mechanism: release NE
- separates 1st and 2nd from 3rd order neuron dysfunction in Horner’s syndrome (positive dilation means 1st or 2nd order)
Cocaine
- class: indirect adrenergic agonist
- blocks reuptake of DA, NE, 5HT
- use to confirm diagnosis of Horner’s
- topical anesthetic, combined vasoconstrictor and local anesthetic
- side effects: sympathetic effects; paranoia, aggression
- rapidly hydrolyzed by plasma cholinesterase
Phenylephrine (Neo-Synephrine)
- class: direct α1-agonist
- dilate pupil for eye exam and cataract surgery
- side effects: extrasystoles, palpitation, HTN, myocardial infarction, trembling, paleness, sweating
- caution in elderly patients: at 10% can cause cardiac side effects
Brimondine tartrate (Alphagan)
- class: direct α2-agonist
- suppresses aqueous humor production through cAMP in non-pigmented ciliary epithelium
- primary agent for treatment of glaucoma
- side effects: may cause follicular conjunctivitis; use with MAOi can cause fatigue/drowsiness
β-blockers used for treatment of glaucoma
- Timolol: β-blocker; contraindicated in CHF, asthma
- Levobunolol: β2-blocker
- Betaxolol: β1-blocker; few side effects
- mechanism: reduce intraocular pressure by reducing aqueous production at ciliary process
- 2nd line treatment of glaucoma
- side effects: bradycardia, hypotension, syncope, CHF, bronchospasm, sexual dysfunction, hyperkalemia
Nifedipine (Procardia)
- class: Ca-channel blocker
- mechanism: increases ocular perfusion at nervehead
- treat low-tension glaucoma
- not widely used
carbonic anhydrase inhibitors
- interferes with active transport of Na through Na-K-ATPase pump→reduced aqueous production
-
dorzolamide, brinzolamide: 2nd line glaucoma therapy
- side effects: red eyes, lid allergies
-
acetazolamide: oral agent for advanced glaucoma and with cataract surgery (only if topical therapy fails)
- side effects: paresthesia, fatigue, drowsiness, depression, diarrhea, met. acidosis, electrolyte changes
MAOIs
- tranylcypromine, phenelzine
- irreversibly inhibit MAOa,b
- treats: depression, anxiety, PTSD, chronic pain, enuresis, bulimia, alcoholism
- important side effects: agitation (rare), delerium→ seizures; HTN crisis with tyramine-rich foods; serotonin syndrome (MAOI + SSRI)
- other side effects: anticholinergic, orthostatic hypotension, sexual dysfunction, weight gain, sedation
Tricyclics
- Desipramine
- Imipramine: active metabolite desipramine
- Amitriptyline (Elavil): active metabolite nortriptyline; high side effects
- Nortriptyline
- block reuptake of NE or 5-HT at varying potencies/ selectivity; also variably block muscarinic, a-adrenergic, DA, and histamine receptors
- treats: depression, anxiety, PTSD, chronic pain, enuresis, bulimia, alcoholism
- not very safe; rarely used
- side effects: sympathomimetic (cardiac arrhythmias and conduction defects, especially at OD), antimuscarinic, orthostatic hypotension, sedation (additive with alcohol), seizures
SSRIs
- Fluoxetine (Prozac): model drug; potent P450 inhibitor
- Paroxetine: more selective for 5HT than fluoxetine; potent P450 inhibitor
- Sertraline, escitalopram, citalopram
- mechanism: inhibit reuptake of 5-HT (and NE to lesser extent)
- treats: depression, anxiety, PTSD, chronic pain, enuresis, bulimia, alcoholism; pre-menstrual dystrophic disorder
- fewer side effects than tricylics, mostly nausea, decreased sexual function
- Serotonin syndrome (with MAOIs)
SNRIs
- Duloxetine (Cymbalta)
- Venlafaxine (Effexor): low risk of side effects
- mechanism: inhibits reuptake of 5-HT and NE
- treats: depression, anxiety, PTSD, chronic pain, enuresis, bulimia, alcoholism
Mirtazapine
- 5HT2a antagonist; also inhibit 5HT reuptake
- treats: depression, anxiety, PTSD, chronic pain, enuresis, bulimia, alcoholism
Lithium
- mechanism unknown; Li depletes 2nd messengers IP3 and DAG, important in a-adrenergic and muscarinic-cholinergic transmission
- treats: anti-manic/mood-stabilizing (bipolar); LT cluster headache prevention
- side effects: drowsiness, weight gain, tremor, polydipsia, polyuria; high levels→neurotoxicity, cardiac toxicity, renal dysfunction
Nalmefene (Revex)
- class: opiod antagonist
- may produce a prolonged withdrawal state (N/V, piloerection, yawning)
N-acetylcysteine (Mucomyst)
- class: antioxidant
- mechanism: supplies sulfhydryl groups to glutathione; improves microcirculation, anti-inflammatory effect
- treats: acetaminophen overdose
Fomepizole (Antizol)
- mechanism: blocks alcohol dehydrogenase
- treats: methanol & ethylene glycol poisoning
- $$$$
Schedule I Hallucinogens
- 5HT2A receptor agonist on Raphe cell body→ inhibition of Raphe Nuclei firing→ increased sensory input; partial dopamine agonist
-
LSD: model hallucinogen; limited studies in psychoanalysis, alcoholism, autistic children, and terminal cancer patients; oxidized in liver
- bad trips (anxiety and panic attacks), flashbacks; no overdoses, birth defects, or chronic psychoses linked to LSD
- Mescaline
- Psilocybin
Phencyclidine (PCP)
- class: dissociative anesthetic
- mechanism: antagonist of ion channel associated with NDMA receptor; agonist at mu opioid receptors
- side effects: violent behavior, coma, seizures, arrest; inexplicable psychoses; dissociation, confusion, ataxia, marked nystagmus
- Long half-life due to being highly lipid soluble and having active metabolites