Age and pregnancy

Question 1

Size drugs cross placents

Answer 1

250-500 easy
>1000 can’t e.g. heparin

Question 2

Category a drugs pregnancy

Answer 2

Metoclopromude, sulfasalazine, cephalexin, nitrofurantoin

Question 3

Category c drugs pregnancy

Answer 3

Oxycodone, heparin, metoprolol

Question 4

Neural tube defect causes

Answer 4

Carbemazepine, valproate (also limb abnormalities)

Question 5

Lithium pregnancy

Answer 5

1st tri ebsteins
3rd foetal tox

Question 6

Body changes with age

Answer 6

decreased: lean body mass, water %, hepatic blood flow, renal mass, albumin
increased: fat %

Question 7

CrCl

Answer 7

(140-age)xweight all / 72xserum creatinine
x0.85 for women

Question 8

Sedative hypnotics in elderly

Answer 8

T1/2 inc by 50-150%

Question 9

Antipsychotic choice in elderly

Answer 9

for sedative phenothiazine e.g. thioridazine (! inc QTc)
non sedative haloperidol or atypical antipsychotic
! clopromazine orthostatic hypotension

Question 10

Cholinesterase inhibitors

Answer 10

for alzheimers
donepezil, galantamine, rivastigmine

Question 11

NMDA non competitive antagonist

Answer 11

for alzehaimers
memantine
decreases glutamate

Question 12

Digoxin in elderly

Answer 12

T1/2 inc 50%, dec vD and clearance

Question 13

!a antiarrhythmics in elderly

Answer 13

quinidine and procainamide inc T1/2 and dec clearance
avoid disopyramide due to antimuscarinic

Question 14

Drugs metabolised more slowly in the elderly

Answer 14

Barbiturates, alprazolam and diazepam, propranolol, quinidine, tolbutamide,

Question 15

Furosemide in pregnancy

Answer 15

fetal electrolyte disturbance and fetal thrombocytopenia

Question 16

water percentage neonate

Answer 16

70-75 (vs 50-60)
40% of body weight is extracellular (vs 20)

Question 17

Young equation paediatric drug dose

Answer 17

adult dose x (age/(age+12))

Question 18

Clarke equation paediatric drug dosing

Answer 18

adult dose x (weight/70)

Question 19

Phase of metabolism affected in elderly

Answer 19

1 (p450) reduction, oxidation, hydrolysis

Question 20

Streptomycin in pregnancy

Answer 20

8th nerve dysfunction

Question 21

Benzos with normal clearance in elderly

Answer 21

oxazepam, lorazepeam (liocaine also ok)