Pharmacology Exam Practice Questions - 5, Part 2

dermregperth's version from 2017-05-21 09:20


17. Finasteride:
Question Answer
Finasteride: Does it affect androgen biosynthesisTrue


18. Topical corticosteroids:
Question Answer
Topical corticosteroids: Does the vasoconstrictor assay correspond well to clinical efficacy and is it an objective testFalse is not an objective test
Topical corticosteroids: Potency of triamcinolone is moderateTrue
Corticosteroids: Does hydrocortisone have cross reactivity with betamethasoneFalse nothing reacts with BM
Topical corticosteroids: Aclometasone - ?correlation with vasoconstriction assayFalse


19. Diltiazem:
Question Answer
Diltiazem: Affects AV nodeFalse it is verapamil that is a strong depressor of AV node
Diltiazem: Prolongs QTFalse
Diltiazem: More peripheral oedema than verapamilTrue
Verapamil: for keloids vs steroids verapamil is superiorFalse steroids superior, verapamil is an alternative
Nifedipine: alter erythrocyte deformationTrue


20. Regarding Efudix:
Question Answer
Efudix: Do patients with DPD deficiency have increased reaction/toxicityTrue (A key enzyme in the metabolic pathway is dihydropyrimidine dehydrogenase (DPD), which converts 5-FU to dihydrofluorouracil (DHFU).) (p518)
Efudix: The structure of 5-fluouracil is a uracil and a fluorideTrue
Efudix: It is misincorporated into RNATrue (5-FU is an antimetabolite. As a structural analog of uracil, 5-FU and its metabolites are misincorporated into RNA and disrupt RNA synthesis. Its metabolites also block the function of thymidylate synthetase, thereby interfering with DNA synthesis as well.) (p518)
Efudix: Is duration to inflammation reaction 2 weeksFalse 5-10 days


21. Regarding Imiquimod: pg476
Question Answer
Imiquimod: It is a non-nucleotideFalse is a non-nucleoSIDE heterocyclic amine
Imiquimod: Its action is on Toll-Like Receptor 2False. Toll-like receptor 7 (p476)
Imiquimod: Does it increase the secretions of IFN-alphaTrue also TNF-a,IFN-y, IL-6, IL1-a, IL-IB, IL-8, IL-12, GM-CSF. G-CSF
Imiquimod: It increases secretion of IL1 and IL6True (Imiquimod induces secretion of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IFN-α, interleukin (IL)-6, IL-1α, IL-1β, IL-8, IL-12, GM-CSF, and G-CSF. It's an activator of Toll-like receptor-7 (TLR-7)) (p476)
Imiquimod: Causes flu like symptoms (more than placebo?)False. Similar to that of a placebo.


22. Regarding Bleomycin: pg 478
Question Answer
Bleomycin: It has direct antiviral effectTrue
Regarding Bleomycin: It affects the S phase of cell cycleFalse acts during the M and G2 phase
Bleomycin: The side effect of eschar uncommonly results in scarringFalse blackened eschar forms. Scarring is uncommon
Regarding Bleomycin: Is Raynaud's phenomenon a possible side effectTrue but is uncommon
Bleomycin: Is it systemically detectable in plasma with concentrations of 1unit/mlTrue (Plasma concentrations of bleomycin after intralesional injection of 1 mg/mL (1 mg/mL = 1 U/mL) have shown detectable systemic levels,84 but to date there are no reports of systemic toxicity.) (p478)


23. Regarding Cantharidin: pg 479
Question Answer
Cantharidin: Application of Cantharidin is painlessTrue (Painless & no scarring) (p479)
Regarding Cantharidin: It forms blisters immediatelyFalse usually forms within 6-24 hours and heals within 1 week
Cantharidin: Does it have a direct viral effectFalse (It has no direct antiviral effect.) (p479)
Cantharidin: Causes mitochondrial apoptosisTrue. Acts by interfering with mitochondria leading to epidermal cell death, acantholysis, and clinical blister formation.
Cantharidin: Is it available in 5% preparations topicallyFalse available 0.7-1%


24. Regarding Ivermectin: pg 135
Question Answer
Regarding Ivermectin: Does it cross the blood brain barrierFalse P-glycoprotein restricts entry of ivermectin across the blood-brain barrier by an ATP-driven efflux mechanism
Ivermectin: It can be used safely in lactationFalse. Crosses into breast milk safety not established
Regarding Ivermectin: Is there increased resistance to this in the Northern Territory due to increased drug metabolism and efflux mechanismsTrue pg 137
Ivermectin: Pharmacokinetics of ivermectin is binds to glutamate-gated chloride ion channels found in invertebrate nerve and muscle cellsTrue- binding results increased permeability of cell membranes to chloride, with hyperpolarisation and death of the parasite


25. Regarding dicloxacillin: pg 63
Question Answer
Dicloxacillin: Is absorption optimised by administration with foodFalse. Better taken 1 hour before or after a meal
Dicloxacillin: Does it have renal adverse effectsFalse this is not mentioned. Most are excreted renally
Penicillin V: safe in pregnancy/lactationTrue. Category B and safe in lactation
Dicloxacillin: Aminopenicillins cause more allergies than dicloxTrue.The first B-lactams reported to cause hypersensitivity reactions was benzylpenicillin with amoxicillin noted to be the most common implicated agent more recently.
Clavulanate: Does clauvulanate improve the effectiveness against beta lactamsTrue


26. Clindamycin:
Question Answer
Clindamycin: Would you rely on sensitivity report panel for sensity to CA-MRSAFalse. Treatment failure may still occur despite an indication of susceptibility on the sensitivity report.
Clindamycin: Provide strong anaerobic coverTrue. Has some cover to P.acnes and Propionibacterium spp. and in the text as covering “a wide variety of anerobes”
Clindamycin: It is bactericidalFalse (Is bacteriostatic to gram +ve cocci, some staph & some strep) (p93)
Clindamycin: Does it have a direct effect on cell wallsFalse. It binds to the 50s subunit of bacterial ribosomal RNA inhibiting ribosomal translocation, resulting in decreased RNA synthesis
Clindamycin: Does it cover most streptococcus speciesTrue. Covers Strep and Staph but not enterococci


27. Clotrimazole:pg 463
Question Answer
Clotrimazole: Does it cover gram positive bacteriaTrue. Covers gram +ve bacteria
28. Topical metronidazole: pg 456
Question Answer
Topical metronidazole: Does it cover m. furfurFalse not mentioned
Topical metronidazole: Does it cover p. acneFalse not active against P.acnes
Topical metronidazole: Does it cover demodex mitesFalse not active against Demodex. Role in rosacea must not be realted to direct killing of the mite.
29. Terbinafine: pg 100
Question Answer
Terbinafine: Is terbinafine metabolised by CYP3A4 isoformTrue. Also metabolised by CYP2C9, 1A2, 3A4, 2C8, 2C19
Terbinafine: Is it renally excretedTrue 70% renally cleared.
Terbinafine: It is fungicidalTrue. Both static and cidal, all the others are only static (i.e. TER-binafine TER-minates)
Terbinafine: Does it penetrate hair shaftFalse? Early detection in the hair by delivery of the drug via the sebum. Later the drug may become incorporated into the hair by hair matrix cells. Pg 102
30. Azelaic acid: pg 457
Question Answer
Azelaic acid: Does it bleach normal skinFalse. Has no depigmenting activity on normal skin.
Azelaic acid: Does it reduce sebumFalse. It does not reduce the rate of sebum production but patients often report gradual reduction in skin greasiness after 1-2 months of treatment.
31. Topical Benzyl peroxide: pg 452
Question Answer
Topical Benzyl peroxide: Does it bleach hair and fabricTrue. Can bleach fabric, hair, and other coloured material.
Topical Benzyl peroxide: Is p. acne resistant to thisFalse. Is bactericidal for P.acnes. In vitro resistance of P.acnes to BP HAS NOT BEEN ENCOUNTERED.
Topical Benzyl peroxide: Is it more likely to cause contact allergy than irritant allergyFalse. Main adverse effect is irritant dermatitis. True contact allergy 0.2-1%.
Topical Benzyl peroxide: The combination of benzyl peroxide and adapalene is more irritating than benzyl peroxide aloneTrue (pg 454). Transient dryness and irritation is more frequent with adapalene/BP than with monotherapy with either agent.
Topical Benzyl peroxide: Is it an oxidiserTrue. Broad spectrum bacteriocidal agent that functions through its powerful oxidising activity.
32. Topical adapalene/retinoids: pg 509
Question Answer
Topical adapalene/retinoids: Is adapalene lipophilicTrue. More lipophilic which enables it to penetrate follicles quickly.
Topical adapalene/retinoids: Is adapalene less photo-labile compared to other topical retinoidsTrue. It is less photolabile than other all-trans retinoic acid.
Topical adapalene/retinoids: Does Tretinoin occur naturallyTrue. Tretinoin is an all-trans retinoic acid and is naturally derived.
Topical adapalene/retinoids: Binding of retinoids to nuclear receptors – uses RAR and RXR which binds to RARETrue. Transported to nucleus by CARBP. RAR and RXR (heterodimerizes and homodimerizes) which then bind to RAREs in DNA to influence gene transcription. (Fig 20-1, p254).
Topical adapalene/retinoids: Is topical Tretinoin safe in pregnancyFalse . Excessive oral vitamin A is teratogenic . No data available on topical all-trans retinol.
33. Systemic retinoids: pg 253
Question Answer
Systemic retinoids: Bioavailability of acitretin is improved with a fatty mealTrue. Oral bioavailability is enhanced with food intake. The effects of a fatty meal is especially great with acitretin and bexarotene.
Systemic retinoids: Acitretin has a possible side effect of elevating serum cholesterol and triglyceride levelsTrue both hypercholesterolaemia and hypertriglyceridemia are common. TG in 50% of patients and 30% patient increased cholesterol.
Systemic retinoids: Elevated transaminases can occur with both acitretin and isotretinoin useTrue (Have been reported in acitretin and isotretinoin. There was no correlation between hepatic transaminase abnormalities and liver biopsy findings.) (p264)
Systemic retinoids: Acitretin is more likely than isotretinoin to cause telogen effluviumTrue more common with acitretin than from etretinate therapy and is much less common with isotretinoin and bexarotene.
Systemic retinoids: The recommended dose of isotretinoin for acne is 0.1mg/kgFalse. Standard dosage range is 0.5-2mg/day see table 20-1 pg 253 or 0.1-1mg/Day in text pg 257 **interesting contradiction!!
Systemic retinoids: Total cumulative dose of isotretinoin for acne vulgaris is 120-150mg/kgTrue. Pg 257.
34. Topical corticosteroids: pg 487
Question Answer
Topical corticosteroids: Rebound syndrome may be characterised by a burning sensationTrue. Pg 497
Topical corticosteroids: Striae are irreversibleTrue. Striae are permanent pg 497 under atrophy heading.
Topical corticosteroids: 7 day use of potent corticosteroids under occlusion may lead to skin atrophyTrue. Atrophy of the epidermis can be seen within 7 days of superpotent TCS (i.e. Clobetasol) under occlusion.
Topical corticosteroids: Tachyphylaxis resolves after a 3-4 day rest periodTrue. Recovery generally occurs after a 3-4 day rest period. Pg 498
35. Prednisone: pg 166
Question Answer
Prednisone: Prednisone induced lipodystrophy may be reversed by decreasing dose to less than 10mg dailyTrue. Prednisolone dosing <10mg/day will generally allow reversal of lipodystrophy.
Prednisone: There is a significant risk of osteoporosis with prednisone between 2.5-5mg dailyTrue. There is a significant risk of CS-induced osteoporotic fractures with pred doses between 2.5-5mg daily
Prednisone: Menstrual abnormalities are not infrequently caused by prednisone 20mg daily True. Up to 40% of premenopausal women on at least 20mg/day experience significant menstrual abnormalities.
Prednisone: There is a significant osteonecrosis risk with prednisone for <3 monthsFalse. Long term (at least 3 months) continuous CS therapy increases the risk of osteonecrosis. Pg 167
36. Systemic corticosteroids effects: pg 146
Question Answer
Systemic corticosteroids effects: Systemic corticosteroids decreases natural killer cell activityTrue pg 146 table 12-2 decreased NK cell activity.
Systemic corticosteroids effects: Increases neutrophils and lymphocytesFalse. Causes apoptosis of lymphocytes. Cannot find statement of neutrophils per se.
Systemic corticosteroids effects: Causes increase in cellular immunity versus humoral immunityTrue pg 146. Has more of an effect on cellular immunity vs humoural immunity.
Systemic corticosteroids effects: Causes increased apoptosis of lymphocytes and eosinophilsTrue (Causes apoptosis of autoreactive T cells (in autoimmune disorders) and neoplastic T cells (in various lymphomas); AP-1 and caspase cascade probably involved in process. Apoptosis of eosinophils with potential implications for various allergic disorders) (Table 12-2, p146).
37. Anthralin/Dithranol: Pg 634
Question Answer
Anthralin/Dithranol: Irritant contact dermatitis is a more common adverse effect of anthralin than allergic contact dermatitis True. Irritant contact dermatitis and staining of clothing, skin, hair and nails are all commonly observed adverse reactions with anthralin therapy. pg 634
Anthralin/Dithranol: Usual initial starting concentration is 0.1% to 1%True pg 634
Anthralin/Dithranol: Can be used with UVBTrue. Has been combined with UVB but does not have to be.
Anthralin/Dithranol: Is also known as crystalipFalse. Crystalip encapsulates the anthralin in a matrix of semi-crystalline monogylcerides which protects the anthralin from oxidation and promotes stability. Chrysarobin is the natural product comes from araroba tree in south America.
Anthralin/Dithranol: Anthralin inhibits monocyte activityTrue. Anthralin inhibits monocyte pro-inflammatory activity and induces extracellular generation of oxygen free radicals.