Drugs Block 4 Flashcards
5-Fluorouracil
Nucleic acid inhibitor used in anticancer therapy; prevents DNA synthesis by inhibiting thymidylate synthase; RNA/protein synthesis NOT affected; cell-cycle and S-phase specific; poor oral bioavailability due to 1st pass-metabolism; must be given intravenously; may see drug resistance via altered drug target. GI ulceration a unique side-effect.
Albuterol
Selective B2 adrenergic agonist; used for fast-acting bronchodilation for acute asthma attacks; only relative selectivity for B2 (over B1) so get cardiac and CNS stimulation.
Aspirin (salicylate)
Non-linear PK, an acid. Aspirin toxicity results in respiratory alkalosis (stimulates resp. center so see a decrease in pCO2) and metabolic acidosis (uncouples oxid. phosph. seeing a drop in bicarb and pH); but the alkalosis wins out. Elimination can be enhanced by alkalinization of the urine by NaHCO3 (alkaline diuresis—ion trapping). Can also treat overdose w/ activated charcoal and hemodialysis.
Atropine
Muscarinic competitive antagonist, highly specific; used to tx bradycardia (works by increasing HR) in emergent situations; also used to counteract bronchoconstriction during intoxication with anticholinesterases. Does NOT change BP. Generally safe to use, but dose-limiting side effects include xerostomia (dry mouth), photophobia, and difficulty in accommodation. Contraindicated in pt’s with glaucoma (can increase intraocular pressure) and prostatic hypertrophy (can cause difficulty in voiding).
Bevacizumab
aka Avastin; an angiogenesis inhibitor used in cancer therapy. Side effects include HTN and GI irritation.
Bleomycin
Anti-tumor antibiotic that produces scission of DNA, cell cycle dependent. Unique side effects include pulmonary fibrosis and hyperpigmentation.
Cisplatin
Alkylating agent (non-classical) that produces adducts leading to DNA damage; cell-cycle independent; may see drug resistance via reduced drug uptake, cellular inactivation, and enhanced DNA repair. Side effects include primarily vomiting, nephrotoxicity, ototoxicity, neurotoxicity, hypersensitivity, and subsequent second delayed malignancy (blood).
Cyclophosphamide
Alkylating agent that targets DNA, anticancer drug; cell cycle independent, acts on both non-dividing and dividing cells; administered orally as a prodrug that becomes activated via hepatic metabolism (P450); its active form has longer plasma t1/2; can see drug resistance via reduced drug uptake, cellular inactivation, and enhanced DNA repair. Side effects include severe myelosuppression, cystitis, and germ cell inhibition.
Cytarabine
Nucleic acid inhibitor that inhibits DNA polymerase and ribonucleotide reductase; cell-cycle and S-phase specific. Side effects include severe myelosuppression and neurotoxicity (high doses).
Doxorubicin
Anticancer drug; intercalating agent that targets DNA, also a topoisomerase inhibitor; has similar cytotoxic effects as ciprofloxacin; metabolized via P450 to active and inactive metabolites, including superoxides. May see drug resistance via drug efflux and cellular inactivation. Side effects include cardiotoxicity (contraindicated with traztuzumab) and severe myelosuppression.
Epinephrine
Adrenergic agonist; many effects: Blood Pressure: low doses decrease BP (Beta 2), high doses increase BP (alpha 1 vasoconstriction, beta 1 positive inotropic); HR initially increases, by will slow once baroreflex kicks in; Vasculature: tissue specific expression of alpha1/beta2 regulates effect of Epi on vasculature. See increased blood flow to skeletal muscle at low concentrations, and decreased flow at high concentrations (Beta 2). In most other tissues/organs, will see vasoconstriction (alpha 1). In Alpha-2 receptors, will stimulate platelet aggregation. Heart: Epi has positive chronotropic, dromotropic, inotropic effects (Beta1); propensity towards arrhythmias. Smooth muscle: via Beta 2 see relaxation of bronchi, GI, uterus (non-pregnant); via Alpha 1 see increased GI sphincter constriction and increased uterine ctxns (pregnant); also see GI smooth m. relaxation with alpha-2. Metabolic: increased glucose/lactate production via liver and muscle glycogenolysis (beta 2); increased FA’s (beta-3), inhibition of insulin secretion (alpha-2), increased O2 consumption. Therapeutic uses: tx of bronchospasm, relief of hypserensitivity rx, prolonged duration of infiltrative anesthesia (vasoconstrictive), restore cardiac activity in cardiac arrest and heart block. Adverse Effects: anxiety, HA, cerebral hemorrhage.
Etoposide
Anticancer drug; a topoisomerase inhibitor; may see drug resistance via drug efflux, altered drug target, or enhanced drug repair. Common side effects (NVD, myelosuppression, alopecia).
Fomepizole
A dispositional antagonist of methanol; blocks alcohol dehydrogenase and prevents formation of toxic formic acid (downstream metabolite). Used to tx alcohol poisoning with ethylene glycol, methanol, etc
Gefitinib (Irresa)
EGFR antagonist used in targeted therapy of cancer; side effects include rash and interstitial lung dz.
Imatinib (Gleevec)
Tyrosine kinase inhibitor used in targeted cancer therapy; metabolized by CYP3A4. Side effects include edema and hepatotoxicity.
Intravenous lipid emulsion
An infusion of IV lipids used to “trap” lipophilic drugs within fat globules in serum so drug is less available to target organ; method to treat lipophilic drug toxicity, such as local anesthetic overdose
Lapatinib
tyrosine kinase inhibitor used in targeted cancer therapy
Methotrexate
nucleic acid inhibitor used as anticancer therapy; variable absorption via oral route; can administer at high (lethal) doses then treat with antidote of reduced folate; also administered intrathecally for optimal CNS levels (administration with mannitol increases permeability of BBB); gets metabolized intracellularly to active polyglutamate form which gets trapped and accumulates; eliminated by renal excretion (so dose dependent on renal fxn). Can see drug resistance via reduced drug activation, reduced drug uptake, and altered drug target. Unusual side effects include stomatitis (mouth inflammation) and nephrotoxicity.
