ExamQ’s 20-21
Leg het werkingsmechanisme uit van lokale anesthetica en welke factoren de werking en
werkingsduur beïnvloeden
Target: signal transmission in neurons
Mechanism of action: block of action potentials: 1) non specifically: volume expansion of the
membrane (benzocaine) 2) specifically: block of voltage dependent NA channel
Action = hydrophilic + hydrophobic pathways
Action = use dependent: 1) increase number open Na channels increase block 2) increase number
inactivated NA channels increase block
Increase block with frequent long lasting AP
Action parameters:
- Rapidity: f(tissue penetration)
- Duration: affinity + diffusion out of the tissue
- Potency: Ph + buffer capacity
Side effects: General depression, CVS, tissue ischemia, arrhythmia and fibrillation, hypersensitivity
5 juist/fout vragen:
sedatie is een type A bijwerking bij H1-antihistaminica
- yes, it is common to feel sedated when the drug can pass the BBB, this is not the case
for 2nd and 3th generation H1-antihistamines!
carbamazepine en een TCA kunnen gebruikt worden in de behandeling van neuropathische
pijn
- in chronic pain TCA and an anti-eppileptic are more effective than an opioid (CAVE is
abuse!)
sublinguaal wordt opgenomen via de vena cava superior en een smelttablet via de vena cava
inferior
- no, melting tablets and sublingual administration will dissolve in saliva skipping
the pharmaceutical phase, so achieving their effect a little faster. Drugs can be
rapidly and directly absorbed into the systemic circulation via venous drainage to the
superior vena cava.
reflextachycardie is een bijwerking van calcium kanaal blokkers (fout: niet van allemaal)
- no, only dihydropyridine CCBs result in a decrease in blood pressure reflex of
increased heart rate and contractility. Verapamil and diltiazem don’t cause it!
GM met halfwaardetijd 4u elke 24u innemen dan bereik je na 5 dagen een steady state (fout)
- Wrong, The dosing interval (τ, i.e. the time between two administrations) is longer
than 4 to 5 half-lives the plasma concentration-time curve consists of subsequent
single doses w/ almost complete elimination of each dose. here longer than 4-5
halftimes!!!!!
steady state concentration: Css = F . (D/τ) . (1/ Cl) = bio-availability .
(Dose/dosing interval) . (1/clearance)
A steady state is reached when the unbound concentrations of the drug in
the tissues and the plasma are equal, so that per time unit, an equal amount
of molecules moves from the plasma to the tissues and vice versa.
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,5 combinaties uitleggen
- glucocorticoïden en NSAIDs may increase the risk of side effects in the gastrointestinal
tract such as inflammation, bleeding, ulceration, and rarely, perforation.
- likeurpraline en een azole AB AB they inhibit aldehyde dehydrogenase (ALDH): makes you
feels sick , nausious, stinks)
- een statine en een fibraat increase the risk for myopathy and rhabdomyolysis
- DOAC en ASA DOAC increases the change of bleeding, so not taken together
- lithium en thiaziden thiazide diuretics increase the reabsorption of lithium and result in
increased serum lithium concentrations -> increased side effects of lithium
H1 antihistaminica
H1-receptor antagonists competitively inhibit the interaction of histamine with the H1-receptor,
thereby inhibiting the vasodilator effects of histamine and preventing the occurrence of edema, flare,
and wheal. H1-antagonists are taken primarily for acute allergies that present as rhinitis, urticaria,
congestion, or conjunctivitis.
Indications: Allergic rhinitis, Allergic conjunctivitis , Allergic dermatological reaction(s), Sinusitis,
Urticaria, Angioedema, Atopic dermatitis, Bronchitis, Motion sickness, Nausea, Vomiting
H-1 antihistamines are further classified according to first and second-generation agents. First-
generation H-1 antihistamines more easily cross the blood-brain barrier into the central nervous
system (CNS), whereas second-generation H-1 antihistamines do not. The first-generation drugs will
bind to both central and peripheral histamine-1 receptors, whereas second-generation drugs
selectively bind to peripheral histamine-1 receptors; this leads to different therapeutic and side
effect profiles.
1e generation: sedation. BBB permeability sedation, drawness promethazine, meclozine,
diphenhydramine, cyproheptadine, ketotifen, dimentindene
2e generation: non sedating. NOT through BBB but cardiotoxic buclizine, loratidine, mizolastine,
ebasstine and cetirizine
3e generation: non cardiotoxic desloratadine, levocetirizine
cholinerge transmissie in het autonoom zenuwstelsel
2 main cholinergic receptor subfamilies: nicotinic and muscarinic acetylcholine receptors;
Effects muscarinic receptors
Pagina 2 van 52
,Effects mediated through nicotinic receptors, in ganglia of autonomic NS:
- CVS: orthosympathetic effects dominate (tachycardia, vasoconstriction and ↑ blood
pressure)
- Higher dosage: depolarizing block (= block of neurotransmission due to continuous
depolarization) causing drop of blood pressure, shock and muscle paralysis (including
respiratory muscles)
DRUGS AND THEIR CLINICAL INDICATIONS
1) increase cholinergic transmission
- muscarinic R agonists: acetylcholine, pilocarpine, carbachol and betanechol
- nicotinic receptor agonists: nicotine and varenicline
- cholinesterase inhibitors: edrophonium, neostigmine, pyridostigmine, physiostigmine,
parathion, sarin, soman and tabun
2) inhibition cholinergic transmission
- antagonists mACHR: thiotropium, atropine, scopolamine and pirezipine
- antagonists nACHR ; d-tubocurarine, parchycurares and leptocurares
anticholinergic side effects and contra indications:
Indications anticholinergics:
- Anesthesia :during intubation and artificial respiration (salivation and secretion ↓) •
suppress reflexes of nervus vagus on the heart during manipulation of the abdomen
(abdominal surgery) • to reduce muscarinic effects of cholinesterase inhibitors
- Eye examination: eucatropine
- Stomatology: salivation ↓
- Asthma and COPD
- Cardiology: extreme bradycardia (overdosage β-blockers or extreme vagal tonus)
- Gastroenterology: GI spasms, colics of gal bladder and urethra, diarrhea
- Central Nervous System • Parkinson’s disease • extrapyramidal effects of antipsychotics •
motion sickness: scopolamine (cholinergic neurons activate vomit center)
benzodiazepines
= anxyoltics = hypnotics = lorazepam, diazepam, clonazepam, midazolam
- Short acting: triazolam, midazolam
- Half long acting: lorazepam, oxazepam, bromazepam
- Long acting: clonazepam, diazepam, flurazepam
Mechanism of action: GABA receptor = PAM = positive allosteric mediator = indirect agonist
of GABA A receptor -> anxiolytic + anti convulsive
Pagina 3 van 52
, Psychotropic effects: sedation, taming effect, anxiolytic effect, sleep inducing effect (by high
dose), anterograde amnesia, conc. Defects and memory defects
Motor effects: muscle relaxation and anti convulsive
Indictaions: anxiety, insomnia, preoperative sedation, delirium tremens, status epilepticus,
muscle spasms and spastic conditions
Indicaties en contra-indicaties van β-blokkers
Beta blockers (pindolol, timolol, acebutolol, propranolol, metroprolol)
- Indications: first choice essential hypertension, angina pectoris, acute myocardial infarction,
stabilizing heart failure, tremor, hyperthyroidism, open angle glaucoma, prevention therapy
migraine, arrhythmias caused by increased orthosympathic tone, anxiolysis
pheochromocytoma and obstructive hypertrophic cardiomyopathy
- Contraindications: bradycardia, cold hand and feet (aggravate Raynauds disease), AV
conductance and AV interference + AV block, heart decompensation, bronchial spasms and
asthma attacks, premature contractions during pregnancy and miscarriage dos not occur, risk
of extended hypoglycemic response in insulin treated diabetics
Leg de geneesmiddelen uit die inwerken op het autonoom zenuwstelsel via de cholinerge zenuwen.
Voornaamste indicaties en bijwerkingen. (bijvraag : iets dat presynaptisch zal werken -> botuline
toxine) see above!
Stellingen bespreken :
Voor Lithium, warfarine en digoxine zullen we TDM doen (bijvraag: wat gaan we meten ->
prothrombine tijd en kaliumconcentraties)
o TDM, therapeutic drug monitoring is needed in all three of them. Protrombine time
is measured (time required between adding different elements to plasma and the
transition from liquid to gel phase (fibrinogen fibrin)) before warfarine.
Voor een overdosis Fentanyl geven we acetylcysteïne
o Naloxone is the antidote for narcotics, such as morphine, dilaudid, and fentanyl.
De farmacokinetische curve van een vloeibare toediening is eerder te vergelijken met deze
van een smelttablet dan een sublinguale tablet
o Correct, curve is identical to melting tablet, sublingual has a faster uptake and higher
plasma concentration than liquid and melting tablet. A melting tablet/liquid is
absorbed in small intestins and not sublingually. (even more low plasma
concentration when using a regular tablet).
Voor de behandeling van parkinsonisme als gevolg van antipsychotica geven we L-dopa.
o Wrong, L-DOPA interacts with antipsychotics neutralizing the activity of L-dopa by
blocking the dopamine receptors switch to other anti-parkinson drug like
Selegiline
Constipatie bij … is een typa A bijwerking.
o Juist, is een verwachte bijwerking
geneesmiddelen bespreken: kort werkingsmechanise, receptor waar ze op werken en voor welke
aandoening ze gebruikt worden ( granisetron, -sartan, diazepam, organische nitraten, fenytoïne).
drug Mechanism of action receptor indication
Granisetron antagonist 5HT3 (serotonin) Anti emtic: vomiting, nausea when
using cytostatics + postoperative
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