Pharm2Exam2 Flashcards
Toxicokinetics
Absorption, distribution, metabolism, and excretion of toxins, toxic doses of therapeutic agents, and/or their metabolites.
Toxicodynamics
Describes the harmful effects of the toxins or toxic doses to vital organ functions. (what the drug does at the receptor level)
DEFG of toxicology
Decontamination
Targeted Elimination
Focused Therapy
“Get toxicologist’s help”
Anticholinergic Toxicity
Decreased PANS
myadriasis, blurred vision, fever, flushed dry skin, AMS, seizures, urine retention/constipation, hypertension, tachycardia
Anticholinergics
Antihistamine (diphenhydramine) Anticholinergic (atropine) Antipsychotic (haloperidol) Antidepressants (TCAs) Environmental (Jimson Weed, Gyromitra)
Physostigmine
Treatment for anticholinergic toxicity
Reversible AChE antagonist
Increases cleavage of ACh at the neuromuscular junction
Used IF: no co-ingestions (TCAs), no seizures, significant AMS, need CV monitoring, may need infusion
Cholinergic Toxicity
Increased PANS activity
muscarinic, nicotinic, and CNS effect
Cholinergics
Organophosphates (pesticides) Carbamates (physostigmine) Iatrogenic (edrophonium) Nerve gas (VX) Mushroom species
Muscarinic Toxidrome
Diarrhea, diaphoresis, urination, miosis, bradycardia, bronchorrhea, bronchospasm, emesis, lacrimation, salivation
Nicotinic Toxidrome
Myadriasis, Tachycardia, weakness, Hypertension, Fasciculations
CNS Cholinergic Tox
Agitation, seizures, coma
Cholinergic Tox treatment
Atropine, Pralidoxime, BZDs
Atropine
Cholinergic tox treatment
1-2 mg IV every 5-10 mins, short acting
May need infusion
Pralidoxime
VX gas antidote
1-2 grams infused over 30 mins
Diazepam
Benzodiazepine - cholinergic tox treatment
Helps CNS effects
Adrenergic Toxidrome
Increases SANS
CNS: AMS, increase temp, seizures
Myadriasis, increased BP and HR, diaphoresis, nausea, vomiting, urine retention
Adrenergic treatment
BZDs, temperature regulation, fluid administration, BP management (verapamil IV, NTG) maybe labetalol - NO BETA only BLOCKERS
BB/CCB toxicity
Myocardium transitions from FFA to glucose substrate = anaerobic metabolism
hypoglycemia
BB: blockade of both B1 and B2 receptors, high dose = blockade of Na channels, decreased entry of Ca and decrease cAMP release, decreased BP and HR
CCB: Decrease SA/AV conduction, reduced CO and BP
Salicylate (ASA) TOX
Antiplatelet Agent
MOA: irreversibly binds COX-1 and inhibits prostaglandin synthesis. uncoupling of oxidative phosphorylation (aerobic metabolism) and disruption of cellular metabolism.
SEs: gastric bleeding, ulcers
Metabolized into salicylic acid and acetic acid metabolites
*triad of hyperventilation and dizziness, GI upset (vomiting), tinnitus
Treatment: gastric decontamination (activated charcoal), LOW Vd, Hemodialysis!
Acetamenophine (APAP)
active metabolite = N-acetyl-p-benzoquinone
Glutathione required to detoxify NAPQI from liver, glutathione depletion = CYP2E1 saturation and tox
Treatment = N-acetylcystine (NAC) usually IV
MOA tox: covalent binding of protein adducts, Kupffer cells and formation of IL, damage is mainly irreversible
Toxic Alcohols
Methanol, ethylene glycol, ethanol, propylene glycol = hyperosmolality AND metabolic acidosis
Isopropranol only = hyperosmolality
HD used as treatment
Unfractionated Heparin
MOA: short half life (2 hours), administered SQ or IV.
Frequent monitoring with activated partial thrombinplastin time (aPTT) UFH tox reversed with Protamine
Protamine
Heparin OD treatment
Slightly basic pH, large dose will result in paradoxical bleeding and CV changes
Ticlopidine
Antiplatelet Agent
ADP antagonist
*not as commonly used
MOA: interferes with the binding of ADP to its receptor on platelets and therefore inhibits the activation of GP IIb/IIIa receptors required for platelets to bind to fibrinogen and bind to each other.
Results in reduced platelet aggregation
Use: Alternative to aspirin in TIA, post-MI, and unstable angina, post-coronary artery stent procedure
Side Effects: GI bleed, neutropenia *RARE side effect of thrombocytopenia
Clopidogrel
Antiplatelet Agent
ADP antagonist
MOA: interferes with the binding of ADP to its receptor on platelets and therefore inhibits the activation of GP IIb/IIIa receptors required for platelets to bind to fibrinogen and bind to each other.
Results in reduced platelet aggregation
Use: Alternative to aspirin in TIA, post-MI, and unstable angina, post-coronary artery stent procedure
Side Effects: GI bleed, neutropenia
Prasugrel
Antiplatelet Agent
ADP antagonist
MOA: interferes with the binding of ADP to its receptor on platelets and therefore inhibits the activation of GP IIb/IIIa receptors required for platelets to bind to fibrinogen and bind to each other.
Results in reduced platelet aggregation
Use: Alternative to aspirin in TIA, post-MI, and unstable angina, post-coronary artery stent procedure
Side Effects: GI bleed, neutropenia
Ticagrelor
Antiplatelet Agent
ADP antagonist
MOA: interferes with the binding of ADP to its receptor on platelets and therefore inhibits the activation of GP IIb/IIIa receptors required for platelets to bind to fibrinogen and bind to each other.
Results in reduced platelet aggregation
Use: Alternative to aspirin in TIA, post-MI, and unstable angina, post-coronary artery stent procedure
Side Effects: GI bleed, neutropenia
Antiplatelet Agents
Aspirin (ASA), ticlopidine, clopidogrel, prasugrel, ticagrelor
Glycoprotein IIb/IIIa inhibitors
Abciximab, Tirofiban, Eptifibatide
Abciximab
GP IIb/IIIa inhibitor
MOA: monoclonal antibody against GP IIb/IIIa receptors on platelets. Prevents the binding of fibrinogen and other adhesive molecules to GP IIb/IIIa = prevention of platelet aggregation. IV administered
Indication: in patients undergoing percutaneous coronary intervention, unstable angina, and post MI
SEs: Bleeding and thrombocytopenia
*Long acting 18-24 hrs
*Hepatic metabolism no dose adjustment for renal dysfunation
Tirofiban
GP IIb/IIIa inhibitor
Indication: in patients undergoing percutaneous coronary intervention, unstable angina, and post MI
SEs: Bleeding and thrombocytopenia
*Short acting 6-12 hrs
*IV and infusion, requires dose adjustment for renal dysfunction
Eptifibatide
GP IIb/IIIa inhibitor
Indication: in patients undergoing percutaneous coronary intervention, unstable angina, and post MI
SEs: Bleeding and thrombocytopenia
*Short acting 6-12 hrs
*IV and infusion, require dose adjustment for renal dysfunction
Direct Thrombin inhibitors
Argatroban, Bivalirudin, Dabigatran
Argatroban
Direct Thrombin Inhibitors
MOA: synthetic manufactured, IV infusion. Half life 0.5-1 hr
Use: patient that do not react to UFH or ADR
SEs: bleeding dependent of dose
*need dose adjust for hepatic dysfunction
*dose titrated to aPTT monitoring
Bivalirudin
Direct Thrombin Inhibitor
MOA: synthetic manufactured, IV infusion, bolus. Half life 25 min. cleared hepatic and some renal
Use: patient that do not react to UFH or ADR, ACS treatment via PCI
SEs: bleeding dependent of dose
*Monitored via ACT
Dabigatran
Direct Thrombin Inhibitor
Novel oral agent
MOA: pro-drug, no need for extensive monitoring and low drug interactions. Target is thrombin inhibition. Low bioavailability, 1/2 life 14-17 hrs, mainly renal clearance
USE: evaluating outpatient use in DVT and PE
Xa Inhibitors
Enoxaparin, Rivaroxaban, Apixaban
Enoxaparin
Xa inhibitor
Rivaroxaban
Xa inhibitor
MOA: inhibit factor Xa, high bioavailability, half life 7-11 hrs, no monitoring required, hepatic and renal clearance
USE: outpatient treatment of DVT and PE
*may have drug ixn with CYP450 3A4 and P-gp
Apixaban
Xa inhibitor
MOA: inhibit factor Xa, medium bioavailability, half life 12 hrs, no monitoring required, mainly hepatic clearance
USE: outpatient treatment of DVT and PE
*May have drug interaction with CYP450 3A4
Fonsaparinux
Synthetic Anticoagulant
Warfarin
Anticoagulant
MOA: inhibition of hepatic-vitamin K dependent clotting factors (II, VII, IX, and X), long acting therapy, primarily protein bound, liver metabolism (CYP2C9 and CYP3A4). S-isomer is more potent and is 2C9, R is 3A4. Crosses placenta CONTRAINDICATED IN PREGNANCY
*Monitored with prothrombin time (PT) and international normalized ratio (INR)
indications: Long-term outpatient anticoagulation for DVT, PE, stroke, AF, and inherited clotting disorders (Protein C and S deficiencies)
AEs/SEs: bleeding, GI bleed, skin necrosis, multiple drug interactions, teratogenic
*Toxicity reverse with vitamin K and blood products
Drug ixn: Acidic molecule so oral cholestyramine can decrease absorption, protein binding drugs can displace (ASA, sulfonamides, and phenytoin) increasing active drug, inducers and inhibitors of CYP2C9 and 3A4 will alter drug concentrations
Phytonadione
Vitamin K clotting agonist
Warfarin OD treatment (?)
aminocaproic acid
Lysine derivative
Inhibitor of fibrinolysis
Tranexamic acid
Lysine derivative
Inhibitor of fibrinolysis
Thrombolytics
Streptokinase, Alteplase, Tenecteplase, Reteplase
USE: Coronary thrombosis, PE, DVT, AMI, Stroke
Streptokinase
Thrombolytic
derived from B-hemolytic streptococcus bacteria (antigenic activity)
MOA: inhibits thrombin, promotes conversion of plasminogen to plasmin
Indication: AMI, stroke, and PE
Alteplase (tPA)
Thrombolytic
Often used in non-hemorrhagic strokes but time of administration is key
MOA: inhibits thrombin, promotes conversion of plasminogen to plasmin = clot lysis Selectively activates plasminogen that is bound to fibrin (selective clot lysis)
Indication: AMI, stroke, and PE (time critical)
*Less hemorrhagic episodes than other thrombolytics due to specificity.
Reteplase
Thrombolytic
MOA: synthetic agent, inhibits thrombin, activates conversion of plasminogen to plasmin = clot lysis
Indication: AMI, stroke, and PE
More use in cardiology
Tenecteplase
Thrombolytic
MOA: Synthetic agent, activates plasminogen to plasmin = clot lysis
Indication: mainly AMI, can be used for stroke and PE too more use in cardiology
Heparin Immune Mediated Thrombocytopenia (HIT)
More severe thrombocytopenia
MOA: antigen-antibody reaction, onset 7-14 days, diagnostic testing, PLT less than 150,000 or >50% decrease from baseline
*Needs additional therapy: DTI (short-term), Warfarin (home)
Heparin Associated Thrombocytopenia (HAT)
MOA: onset less that 7 days, temporary, requires supportive care but no additional therapy, may continue heparin therapy and monitor PLT
Rapid Preparation Insulin
Drugs: Lispro, Aspart, glulisine
MOA: rapid onset of action/control, but do not last long. ~4 hrs, control for meal time
Short Preparation Insulin
Regular insulin
MOA: onset of 30 mins, SQ administration or IV
Intermediate preparation Insulin
Neutral Protamine Hagedorn (NPD) or Isophae
MOA: onset ~2 hrs, duration of 4-12 hrs
Long preparation insulin
Drug: Glargine and Detemir
MOA: Slow onset (1 hr), and lasts 12-24 hrs