Review of Pharmacology - 9E (2015)

Review of Pharmacology
203. Ans. (b) Propanolol; (d) Physostigmine (Ref: KDT 7/e p18-19)
• Lipid soluble drugs can penetrate blood brain barriers (BBB). These include
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Levodopa
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Physostigmine
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Organophosphates
• Streptomycin, neostigmine, hexamethonium, glycopyrrolate, dopamine cannot cross BBB.
204. Ans. (b) Quinine; (c) Chloroquine (Ref: KDT 6/e p908)
• Primaquine is avoided during pregnancy, because fetus is G-6PD deficient; thereby can cause hemolysis.
• Tetracyclines are contra-indicated in pregnancy and in children.
• Sulfonamides (antifolate) are also contra-indicated in pregnancy.
205. Ans. (a) Antihistaminics; (b) Antithyroid drugs; (c) Penicillin; (d) Diazepam; (e) Antiepileptics (Ref: KDT 6/e p911-914)
• Benzodiazepines cross placenta and are secreted in milk.
• Antithyroid (e.g. carbimazole), antihistaminics, penicillin and antiepileptics are also secreted in milk.
206. Ans. (d) An antihypertensive with a plasma half life of 3 hours (See below)
Sustained release formulations of a drug are used for the drugs having short duration of action requiring prolonged administration.
General Pharmacology
• PSVT is an acute condition and requires a short and fast acting drug. Adenosine is therefore, the drug of
choice for this condition.
• Option (b) describes a drug having long half life (24 hours). This drug need not be administered as sustained
release preparation.
• For a hypnotic drug, action required is brief i.e. to induce sleep. Therefore, it should not be given as a sustained
release preparation.
• Treatment of hypertension is life long. Drug with half life of 3 hours, needs to be administered several times
a day, therefore sustained release oral dosage form is best utilized for this drug.
207. Ans. (c) Ion trapping of acidic drugs occur in pregnancy: (Ref: Goodman & Gilman 11/e p9-10)
• Heparin and insulin are anticoagulant and antidiabetic drugs of choice, respectively, in pregnancy, because these
have minimum entry across placenta.
• Fetal plasma is slightly more acidic than that of mother (pH 7.0 as compared to 7.4 of mother), so ion trapping of basic
drugs occur.
• Placenta contain P-glycoprotein that can act as an efflux pump for drugs.
• Placental transfer of most drugs is greater in late pregnancy than in early pregnancy because uterine circulation increases
and trophoblastic layer becomes thinner as the pregnancy advances.
208. Ans. (c) Lithium (Ref: KDT 6/e p435)
209. Ans. (c) Renal clearance (Ref: Katzung 11/e p1039)
210. Ans. (a) Orphan drugs (Ref: KDT 6/e p6)
211. Ans. (b) Dopamine (Ref: KDT 6/e p415
212. Ans. (c) Radioactive isotopes (Ref: KDT 6/e p252)
213. Ans. (a) Glycopyrolate (Ref: KDT 6/e p110)
214. Ans. (b) Insulin (Ref: Katzung. 11/e p734)
Answers of recent Questions asked by National Board
1. Ans (b) Allergic effect of the drug (Ref. KDT 7th/83)
2. Ans (b) Penicillin (Ref. KDT 7th/56)
3. Ans (a) Valproate (Ref. KDT 7th/26)
4. Ans (a) Enalapril (Ref. KDT 7th/502
5. Ans. (d) Physiological antagonism (Ref: KDT 7/e p58)
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