Drug excretion

Question 1

Drugs secreted into bile will ultimately pass through

Answer 1

the large intestine

Question 2

Examples of drugs secreted by the large intestine

Answer 2

Vancomycin
Vincristine

Question 3

Acid/Basic drugs are excreted in the saliva as a result of

Answer 3

Basic drugs as a result of passive diffusion

Question 4

Examples of drugs excreted by the tongue

Answer 4

Phenytoin
Diazepam
Theophylline
Caffeine
Lithium

Question 5

What qualities should drug molecules have to be able to pass from plasma across the eccrine and lachrymal glands

Answer 5

Lipophilic
Non-protein bound
Unionized

Question 6

Drug excreted in tears

Answer 6

Cytarabine

Question 7

Excretion through the lungs occurs mainly with

Answer 7

Anaesthetics

Question 8

Through the skin/sweat (7)

Answer 8

1. Alcohol
2. Antipyrine
3. Benzoic acid
4. Cocaine
5. Salicylic acid
6. Lead
7. Mercury

Question 9

Through the breast or breast milk

Answer 9

Aspirin

Question 10

Drugs excreted through the hair

Answer 10

Phenobarbital
Methamphetamine
Methoxyphenamine

Question 11

Renal excretion =

Answer 11

GF - TR + TS

Question 12

Tubular reabsorption occurs by passive diffusion and requires

Answer 12

Lipid solubility

Question 13

Features of Tubular secretion

Answer 13

Carrier mediated
Independent of size
Independent of protein binding

(Excretes most drugs~80%)

Question 14

3 compounds not excreted by GF

Answer 14

Heparin(high m.w)
Albumin(high m.w plasma protein)
Warfarin(highly protein-bound)

Question 15

Water, lipid soluble drugs and other lipid soluble drugs are reabsorbed at the PCT T/F

Answer 15

DCT

Question 16

Tubular reabsorption occurs via passive diffusion from the tubules into

Answer 16

The peritubular capillaries

Question 17

Formula for renal clearance

Answer 17

CLr=Cu/Cp x Vu

Question 18

Types of half life

Answer 18

Biological
Plasma

Question 19

Biological t1/2 is the time taken for a substance to lose half of its

Answer 19

Physiological
pharmacological
radioactive activity

Question 20

Arrange these drugs according to their plasma t1/2
Methadone. Noradrenaline, Fluoxetine

Answer 20

Noradrenaline 2mins
Methadone 15hrs
Fluoxetine 6days

Question 21

Factors affecting drug excretion

Answer 21

Lipid solubility
pH
Enterohepatic cycling
Particle size
Protein binding
Drug interaction
Renal diseases

Question 22

Compounds used for alkalization

Answer 22

Sodium bicarbonate
Acetazolamide
Potassium citrate

✨SAP✨

Question 23

Compounds used for acidification

Answer 23

Ammonium Chloride
Sodium phosphate
Potassium phosphate

Question 24

Basic drugs

Answer 24

Morphine
Histamine
Serotonin
Dopamine
Pethidine

Question 25

Acidic drugs

Answer 25

Aspirin Penicillin Methotrexate Indomethacin Frusemide Thiazide diuretics AMPIT with an F

Question 26

Lipid solubility increases/decreases excretion

Answer 26

Decreases

Question 27

Enterohepatic cycling increases/reduces drug excretion

Answer 27

Reduces

Question 28

Drugs that undergo enterohepatic cycling

Answer 28

Tetracycline Chloramphenicol Flurbiprofen Leflunomide Colchicine Digitoxin Phenytoin Oestradiol

Question 29

What drug inhibits the excretion of penicillin

Answer 29

Probenecid (by competing with it for tubular secretion at the proximal tubule)

Question 30

Normal GFR

Answer 30

100-130

Question 31

GFR in kidney disease

Answer 31

less than 60

Question 32

GFR in kidney failure

Answer 32

15

Question 33

Formula for absolute bioavailability (F)

Answer 33

AUCoral x 100% / AUCiv when dose are same AUCoral x DOSEiv x 100% / AUCiv x DOSEoral when dose are different

Question 34

AUC =

Answer 34

1/2(l + b)h

Question 35

Relative bioavailability

Answer 35

AUCtest / AUCstandard

Question 36

To be bio equivalent the difference in relative bioavailabilities of two related drugs must not exceed

Answer 36

+/-20%

Question 37

2 main types of drug interaction

Answer 37

Pharmacokinetic DI pharmacodynamic DI

Question 38

Example of alteration of absorption

Answer 38

Calcium(Antacids) bs tetracycline

Question 39

Alteration of metabolism

Answer 39

Efavirenz vs artemether/lumefantrine (Efavirenz induces CYT P3A4 enzyme which metabolizes the anti malarial drug hence reducing their plasma conc.

Question 40

Types of pharmacokinetic drug interaction

Answer 40

Alteration of absorption Alteration of metabolism

Question 41

Types of Pharmacodynamic Drug interaction

Answer 41

Additive toxicity Therapeutic failure/Reduction in efficacy

Question 42

Example of additive toxicity

Answer 42

Concomitant use of NSAIDs and glucocorticoids increases the risk of gastric bleeding and worsens peptic ulcer disease

Question 43

Example of therapeutic failure

Answer 43

Concomitant administration of ascorbic acid or other antioxidants with ACT in the treatment of malaria