Beardsley Material Flashcards by Matthew Stringham

High risk patients for drug interactions

elderly, young, sick, multiple diseases, multiple drug therapies, renal or liver impairment

How well did you know this?

Not at all

Perfectly

What are three general classes of drug-drug interactions?

Preadmin
Pharmacokinetic
Pharmacodynamic

How well did you know this?

Not at all

Perfectly

What are two characteristics of high risk drugs for interactions?

Low (narrow) therapeutic index

2. Recognized enzyme inhibitor or inducer

How well did you know this?

Not at all

Perfectly

What are 4 types of pharmacokinetic drug interactions?

Drug absorption
Drug displacement (protein binding)
Drug biotransformation (metabolic)
Drug excretion (from cells or body)

How well did you know this?

Not at all

Perfectly

What are 5 general mechanisms of drug absorption interactions?

Change in GI pH
Drug binding in GI tract
Change in GI flora
Change in GI motility
Malabsorption caused by other drugs

How well did you know this?

Not at all

Perfectly

What happens if tetracyclines and quinolone antibiotics are taken with calcium food, vitamins and supplements?

Chelate the divalent and trivalent cationsto make acomplex that is poorly absorbed

How well did you know this?

Not at all

Perfectly

If you administer Warfarin and NSAIDs together, their competition for protein receptors causes what?

More warfarin to be active

How well did you know this?

Not at all

Perfectly

If a drug is an enzyme inducer, it will do what to the other drug?

Decrease its effects

How well did you know this?

Not at all

Perfectly

If a drug is an enyzme inhibitor, it will do what to the other drug?

Increase its effects

How well did you know this?

Not at all

Perfectly

What do all parts of CYP450 nomenclature mean?

Cyp = superfamily/ 3 - family/ A = subfamily / 4 = individual gene

How well did you know this?

Not at all

Perfectly

Cytochrome enzyme involved in the greatest number of drug biotransformations

CYP3A4

How well did you know this?

Not at all

Perfectly

5 CYP enzymes responsible for drug metabolism

CYP2E1
CYP1A2
CYP2C9
CYP2D6
CYP3A4

How well did you know this?

Not at all

Perfectly

Where is the cytochrome P450 system located?

The lipid bilayer of smooth ER and hepatocytes in liver and enterocytes of small intestine

How well did you know this?

Not at all

Perfectly

What CYP450 enzyme will ciprofloxacin inhibit, and what drugs can then potentiate?

CYP1A2, tacrine, theophylline, imipramine, flu

How well did you know this?

Not at all

Perfectly

Which drug would be potentiated if CYP1A2 was inhibited by erythromycin?

Theophylline

How well did you know this?

Not at all

Perfectly

Grapefruit juice inhibits which CYP450 enzyme?

CYP34A

How well did you know this?

Not at all

Perfectly

2 Drugs metabolized by CYP2D6 where the inhibition of the enzyme decreases the drugs’ net effects

Tramadol

2. Codeine

How well did you know this?

Not at all

Perfectly

What are 2 kinds of general drug excretion interactions?

One drug impairs the renal excretion of another

2. Affects on permeability of the glycoprotein

How well did you know this?

Not at all

Perfectly

What occurs if thiazide diuretics are given to someone on Lithium?

Will cause lithium to be retained and accumulated

How well did you know this?

Not at all

Perfectly

Which CYP 450 is affected by the same drugs that PGP is?

CYP 34A

How well did you know this?

Not at all

Perfectly

What are 2 possible specific interactions that opiates can have with local anesthetics?

Opiate induced respiratory acidosis

2. Elevation arterial carbon dioxide tensions leading to convlusions

How well did you know this?

Not at all

Perfectly

Drugs to be aware of when administering prilocaine to minimize the induction of methemoglobinemia

Nitroglycerine
Dapsone
Solfonamides
Phenacetin

How well did you know this?

Not at all

Perfectly

Possible side effect of giving patient epinephrine while on a beta blocker

Their B2 vasodilation is blocked and EPI stimulates the A1 vasoconstrictors unopposed causing hypertension

How well did you know this?

Not at all

Perfectly

What is a concern for a patient taking NSAIDS and SSRIs?

Increased bleeding risk due to decreased platelet aggregation

How well did you know this?

Not at all

Perfectly

Is the NSAID/SSRI interaction additive?

No it is synergistic

How are local anesthetics different from general anesthetics?

Local applied to target site and block pain by depressing peripheral nerves and their axonal conduction while general administered sytemically and depresse CNS and block pain by stopping transmission across synapses

What are 8 properties of ideal local anesthetic?

1. Nonirritating 2. No permanent alteration of nerve 3. Low systemic toxicity 4. Effective topically or by injection 5. Short onset time 6. Appropriate duration of action 7. Non-allergenic 8. Sufficiently potent

What are 3 domains of a local anesthetic?

1. Lipophilic 2. Alkyl link 3. Hydrophilic

What domain determines the anesthetic classification, its metabolism and its toxicity?

The alkyl group (amide or ester)

What is the primary determinant of local anesthetic potency?

Lipid solubility (the more lipid soluble, the more potent)

What is the primary determinant of duration of action of local anesthetics?

Protein binding (great the protein binding, the longer the duration of action)

What are the 2 most influential determinants of onset of action of local anesthetics?

Neuron Fiber size and pKa of local

What is the most common site of action for local anesthetics?

Bind receptor in the sodium channel to block sodium influx

What is pKa?

The measure of inherent acidity of alkalinty of a molecule. it is the pH at which the cation and the base species are equal

Only what form of the anesthetic binds the receptor?

Ionized form (cation = positively charged)

Which fibers are generally affected by local first: pain or motor?

Pain because sensory fibers normally are smaller than motor

What happens to local pH in inflamed tissue and its affect on the speed of onset for local?

Tissue pH decreases. This causes more cations of the local (i.e. less base) which increases the amount of time it takes to diffuse, and takes longer for onset

How are ester anesthetics (e.g. Procaine) metabolized?

In blood by pseudocholinesterase

How are amide anesthetics metabolized?

Liver

Which class of local anesthetic would more likely produce a hypersensitivity reaction?

Ester

What metabolite is the likely cause of the hypersensitivity reaction?

p-aminobenzoic acid (PABA)

What percentage of patient is likely to have a hypersensitivity reaction to local?

less than 1 percent

What is the major organ of excretion for both ester and amide locals?

Kidneys: urine and feces as various metabolites

What are 5 Amide local anesthetics

``` (First part has an I in it) Lidocaine Etidocaine Mepivicaine Bupivicaine Prilocaine ```

What are 5 ester local anesthetics?

``` (No I other than the "caine" part) Procaine Benzocaine Propoxycaine Tetracaine Cocaine ```

Where do tetrodotoxin and Saxitoxin (local anesthetic-like poisons) bind?

Irreversibly bind external membrane of nerve near the sodium channel

What are 7 general factors influencing Local Anesthetic Toxicity?

1. Drug Type 2. Concentration 3. Route of administration 4. Rate of injection 5. Vascularity 6. Patient's weight 7. Rate of metabolism and excretion

What is methemoglobinemia?

Drug-induced cyanosis caused by a metabolite oxidizing Ferrous (Fe+++) oxygen-carrying hemoglobin to Ferric (Fe+++) non oxygen-carrying hemoglobing (methemoglobin)

What is the majory local anesthetic that can cause methemoglobinemia and the metabolite that causes it?

Prilocaine, O-toluidine

What is the treatment for methemoglobinemia?

Slow IV administration of methylene blue which reduces methemoglobin to hemoglobin by acting as an electron receptor

What are the components of oraqix?

1:1 Lidocaine to Prilocaine (2.5% Lidocaine, 2.5% Prilocaine, 92% water, 3% inert stabilizers)

What are 2 primary indications for Bupivicaine?

1. Lengthy dental procedures | 2. Post-operative pain management (longer onset but also longer duration)

What is the general idea of an isomer approach?

The (+) and (-) isomers of a molecule may have different properties though they have the same number and kind of atoms. One isomer can be isolated and exploited to advantage.

What is an example of the isomer approach?

(-) istom of bupivicaine is less cardiotoxic than racemic bupivicaine. Therefore, market (-) isomer as Ropivicaine.

What is the term for a mix between a local anesthetic with an absorbable iodized fatty acid (used to use peanut oil)?

Iophendylates Depot Prep

What is the term for a mix between a local anesthetic with hydrophobic triglycerides and encapsulating in a layer of phospholipids?

Lipospheres Depot Prep

What is the term for a mix between local anesthetic, a lipid, and an emulsifier sonicated in a liquid producing micelles of lipid bilayer called liposomes, containing local anesthetic and water within their cavity?

Liposome depot prep

Tetraethylammonium (TEA) is what?

Selective potassium ion channel blocker

What are 2 biotoxin local anesthetics?

1. Tetrodotoxin | 2. Saxitotoxin

Where do tetrodotoxin and saxitoxin bind and what do they block?

Bine to external membrane, irreversibly block sodium channels

What is the positive aspect of biotoxins?

Selective for sodium channels, and selective to block neural over cardiac tissue

Beardsley Material Flashcards

(61 cards)