misc Flashcards
Class: hypericum antidepressant
MOA: probably inhibits reuptake of NE, 5-HT and DA; downregulates expression of cortical beta-adrenergic receptors and upregulate expression of 5-HT2 receptors
Use: mild to moderate depression; tx of HIV & basal & squamous cell carcinoma
Adverse: photosensitization, hypomania, mania & autonomic arousal
Interactions: antidepressants and stimulants increase risk of serotonin syndrome
St. John’s wort
MOA: muscarinic blocker
-blocks cholinergic muscarinic neurons of basal ganglia
Use: Parkinsons disease
Adverse: sedation, mydriasis, urinary retention, constipation, confusion, dry mouth
benztropine (Cogentin)
trihexyphenidyl (Artane)
Class: Indole derivative
MOA: selective 5-HT1b/1d agonist that causes constriction of intracranial blood vessels
Use: acute migraine
Metab: peak at 12 min if admin subcu, 1-2 hours if taken orally
Adverse: coronary artery vasospasm, transient myocardial ischemia, arterial and ventricular arrhythmias, MI, parasthesias, asthenia, fatigue, flushing, pressure tightness or pain in the chest neck and jaw; drowsiness; nausea; sweating
Contraindication: ischemic or vasospastic CAD, cerebrovascular or peripheral vascular disease, hemiplegic or basilar migraines, ischemic bowel disease, uncontrolled HTN
sumatriptan
Imitrex
nucleoside analog
acyclic guanosine derivative with clinical activity against HSV-1, HSV-2 and VZV
10 times more potent against HSV-1 and HSV-2 - shortens duration of symptoms of genital herpes by 2 days, lesion healing by 4 days and viral shedding by 7 days. Given in organ transplant patients to prevent reactivation of HSV infection.
DOC: herpes simplex encephalitis, neonatal HSV infection, and serious HSV or VZV infections
MOA: inhibition of viral DNA synthesis by competition with deoxyGTP for viral DNA polymerase, resulting in irreversibly binding to DNA template, followed by chain termination
activated by 3 phosphorylation steps:
1. phosphorylation by viral thymidine kinase
2. & 3. phosphorylation by host cell enzymes
Because first step requires viral enzyme, the metabolite accumulates only in virally infected cells
Metab: low oral availability; topical high concentrations in herpetic lesions; available in IV
Diffuses into most body fluids, including CSF
Clearance: glomerular filtration
Interactions: probenecid and cimetidine decrease clearance and lead to nephrotoxicity; somnolence with zidovudine
Side Effects: nausea, diarrhea, headache, renal toxicity (IV form), neuro effects (tremors, delirium, seizures)
Resistance: alteration of viral thymidine kinase or DNA polymerase
Can use Foscarnet, cidofovir and trifluridine for resistant strains, as they do not require phosphorylation by thymidine kinase
Acyclovir
Zovirax
MOA: thought to activate 5-HT1D receptors on intracranial blood vessels, causing vasoconstriction
Use: migraine
ergotamine
partial agonist of nicotinic ACh receptors with greater affinity than nicotine
more effective than bupropion for smoking cessation
Adverse: weight gain, exacerbation of pre-existing psychiatric conditions, agitation, hostility, depression, suicidal ideation and behavior
varenicline
Chantix
