MOA of drugs Flashcards
Heparin
Effects on triglycerides?
Bounds lysine on AT III enhancing AT III’s ability to neutralize thrombin (factor II) and factors IX, X, XI, XII
Increase release of lipoprotein lipase (LPL) with insulin (decrease TG), then an effective alternative Tx for high triglycerides induced acute pancreatitis
Heparin decreases TG and Cho
Aspirin
Irreversibly inhibits production of thromboxane by inhibiting COX (arachidonic acid —>PGH2)
Antiemetics MOA
- 5HT3 antagonist: ___, ___, ___
- 5HT4/serotonin agonist: ___, ___, ___
- Dopamine-2 antagonist: ___, ___, ___
- NK-1 receptor antagonist: ___
- Proton pump inhibitor: ___ (inhibit P450)
- H2 antagonist: ___, ___ (inhibit P450), ___
Antiemetics MOA
- 5HT3 antagonist: ondansetron, metoclopramide, cisapride
- 5HT4/serotonin agonist: cisapride, metoclopramide, erythromycin
- D-2 antagonist: metoclopramide, domperidone, chlorpromazine
- NK-1 receptor antagonist: maropitant
- Proton pump inhibitor: omeprazole (inhibit P450)
- H2 antagonist: famotidine, cimetidine (inhibit P450), ranitidine
What microorganisms are resistant to penicillin and beta-lactam?
Pseudomonas and Mycobacterium
Mycoplasma??
Four anaerobic antibiotics
amoxicillin, cephalexin, metronidazole, clindamycin
NSAID which causes irreversible COX inhibittion
Aspirin
Omeprazole
Irreversibly binds H-K ATPase at parietal cell
Inhibits CYP 450
Decreased CSF production
Cyclosporine
Binds to cyclophilins which associated with Ca dependent calcineurin-calmodulin complexes
Stopping dephosphoorylation of NFAT
Decreases IL-2 production in G0 phase T cells
Also cyclosporine can inhibit insulin release
Allopurinol
Xanthine oxidase inhibitor
Dalmatians, English bulldogs, liver dysfunction
Dalmatians thought to be due to uric acid transport defect which prevents movement of uric acids into hepatocytes for conversion to allantoin by uricase.
4-MP
Competitively inhibits alcohol dehydrogenase preventing formation of oxalic acid if given early to EG ingestion cases
What organisms not killed by Clavamox?
Enterococci
Which skin layer prevents drug absorption?
Stratum corneum
What are the effects of epinephrine on bronchi, vessels iris?
Bronchi: dilation of bronchi
Vessels: vasodilation of muscle/liver (beta2), vasoconstriction of other vessels (beta1)
Iris: mydriasis
Most common neurotransmitter in sympathetic post-ganglionic nerve ending?
NE
What will heparin lower with blood work?
Triglycerides and cholesterol due to increased LPL with heparin
What drug is a platelet adhesion inhibitor?
GPIIb/IIIa inhibitor
GP = glycoprotein
Levetiracetam
Inhibits SV2A which is a voltage-gated Ca channel located on membrane on synaptic vesicles in the neuronal and endocrine system
Mycophenolate mofetil (MMF)
Inhibits inosine monophosphate dehydrogenase (IMPDH) necessary for purine synthesis
The rate-limiting enzyme in the de novo synthesis of guanosine nucleotides
Azathioprine
purine analogue that inhibits RNA and DNA synthesis
decreases T cell mainly
may decreases CD8 and NK cells (cell mediated immunity effect)
functions as competitive purine antagonist
PPA (phenylpropanolamine)
Stimulate alpha receptors in urethral sphincter
Used for urinary incontinence (Proin)
Selective norepinephrine releasing agent
Phenobarbital
GABA mimetic
Causes influx of Cl into the cell, creating a more negative RMP; harder to depolarize
AE: necrolytic dermatitis, decreases total and free T4
Potassium bromide (KBr)
Bromide ions compete with Cl transport and membrane hyper polarization and raising seizure threshold
High dietary Cl will enhance renal excretion of KBr
AE: allergic pneumonitis in cats which can be fetal
Zonisamide
Inhibits Na and Ca channels and increases GABA effects
Increases total T4
T-type Ca channel, voltage gated Na channel inhibitor, facilitate dopaminergic/serotonergic neurotransmitter
Felbamate
Dicarbamate that blocks NMDA-mediated excitation, potentate GABA-mediated inhibition, inhibits voltage-sensitive Na and Ca channels
Prazosin
alpha 1 antagonist that works on internal and external urethral sphincter
Tx for overstimulation of nicotinic and muscarinic receptors?
2PAM
2PAM competes with organophosphates which inhibit Achetylcholinesterase) and dissociated them.
Atropine and glycopyrolate only work at muscarinic receptor.
No pure nicotine receptor inhibitor.
Ursodeoxycholic acid (UDCA, Actigall)
UDCA is secreted into bile, it becomes protonated, leaving one HCO3 ion.
Protonated UDCA becomes reabsorbed into hepatocytes resulting in the net secretion of one HCO3 ion which draw water into the bile.
Also has immunomodulatory effects; inhibition of IL-1, IL-2, Ig from B cells
Replaces more toxic hydrophobic bile acids with hydrophilic bile acid.
Dirlotapide
Inhibits release lipoproteins and reduces fat deposition. Used for weight loss (Slentrol)
Pentoxyphylline
Non-specific PDE inhibitor
Thienopyridines (Clopidogrel, Plavix)
Inhibits ADP induced platelet aggregation without effects on COX
Oclacitinib MOA and side effects
JAK 1 and 3 inhibitor
Inhibit IL-31
AEs: vomiting and diarrhea in 5%
Trilostane
Inhibits 3-beta hydroxysteroid dehydrogenase
pregnenelone to progesterone
Erythromycin
motilin agonist
5HT4 agonist
Misoprostol
PGE1 analogue
inhibits secretion of gastric acid
increase bicarb
Prednisone
Inhibits phospholipase which concerts phospholipids to arachidonic acid
Stabilize membranes
Inhibits chemotactic factors
Inhibits elastase
Methimazole
Inhibits thyroperoxidase
No oxidation of iodide to iodine
GI AEs in 10% of cats
Excoriation AEs in 2-3% of cats in face and neck
Neutropenia and thrombocytopenia in 3-9% of cats
Leflunomide
pyrimidine synthesis inhibitor
inhibits mitochondria enzyme dehydroratate dehydrogenase and cell arrest in G1 phase
Drug interaction between enrofloxacin and theophylline
Reduce theophylline dosage by 30% due to enro increase the bioavailability of theophylline
Nitroimidazole
redox reaction crease DNA damage?
Diaminopyrimidine
inhibits production of THF doom DHF?
Diazoxide
Inhibits insulin secretion by opening ATP sensitive potassium channel of beta cells of pancreas
Tx of choice for insulinoma
How reverse diazepam?
Benzodiazepine reversal with flumazenil
Gabapentin
Binds to voltage gated Ca channel
Release of excretory neurotransmitter is inhibited by decreasing influx of Ca
Felbamate
Anti-convulsant
NMDA inhibitor, GABA mediate neuronal inhibitor
Increases the activation of Na channel and decreasing sustained high frequency firing of action potential, then reduce excretory neurotransmitter
Maropitant
Neurokinin (NK) 1 receptor antagonist
Transposons
Allows transfer of DNA from plasmid to chromosome (Ab resistance)
Transdermal methimazole
Transdermal formulation in pluronic lecithin organogenesis (PLO)
Absorption across stratum corneum
Significantly lower GI AEs (4% of cats) compared to oral methimazole
Methotrexate
Folic acid analogue
Competitively inhibits DHFR (dehydrofolate reductase) and depletes the pools of reduced folates
Reduced folates are required in conversion of dUMP to dTMP and for purine synthesis, then inhibits DNA synthesis
Hydroxyurea
Inhibits ribonucleotide reductase and resulting in depletion of deoxyribonucleotide pools
Which lesion does gentamicin damage in the kidney?
Proximal tubule
Amphotericin B
Irreversibly binds to sterole, causing membrane pores to form rapidly effective. Also has immunomoduratory effects.
Nephrotoxic
Theophylline
Inhibits PDE, causing smooth muscle relaxation, improving mucociliary clearance, and improve diaphragm contractility.
Drug interaction with Baitryl
Antagonized by beta blockers
Ca gluconate in hyperklemia
Raises threshold potential of cardiac myocyte to restore gap between resting and threshold.
What drugs does phenobarbital increase clearance?
oral antiicoagulants, chloramphenicol, doxycycline, steroids, beta blockers, theophilline, metronidazole.
Rifampin decrease the effects of phenobarbital.
Estrogen toxicity
Direct effect on one marrow though estradiol-1-beta receptor, induction of myelopoiesis inhibitor factor.
ABX penetrates BBB
Metronidazole, TMS, chloramphenicol, erythromycin, azithromycin
Weak penetration: 3rd generation of cephalosporin, rifampin, fluoroquinolone, doxy, tetracycline, penicillin, clindamycin
Acarbose
Alpha glucosidase inhibitor
Competitive inhibitor of alpha glucosidase enzyme
Glipizide
Sulfonylureas
Improve insulin secretion from pancreatic beta cells
