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Flashcards in Prescribing in special cases Deck (16):
1

ACE-I affect K levels how?

Hyperkaleamia

2

Diuretics affect K levels how?

Hypokalaemia. (Except for K sparing, diuretics. For these combine with loop diuretics).

3

Can you co-prescribe ACE-I and diuretics?

Yes, they can cancel each other out, which is great. But spironolactone and amiloride are to be avoided, since they are potassium sparing. MONITOR MONITOR

4

Loop diuretics?

Furosemide
Bumetanide

5

K sparing diuretics?

spironolactone and amiloride

6

Thiazides?

Chlortalidone and indapamide

7

Renal failure: how do you prescribe?

Check BNF and adjust dosage for drug
or
Use alternative approach

8

Why might using an alternative approach for renal impairment be helpful?

Gentamycin: increase the dosage interval
tolbutamide as a choice sulphonylurea: is short-acting, doesn't accumulate as much
Hypertension: amlodopine, non-renally excreted

9

Metformin and Renal impairment

Absolutely no if eGFR too low, metabolic disturbances, won't clear.

10

Thiazide diuretics and Renal impairment?

won't work, depend on renal function to function itself

11

Key issue with prescribing in pregnancy?

Everything, bar heparins, crosses placenta
Assume that all females of child-bearing age are pregnant unless you know otherwise (could become pregnant whilst taking this medication). Window in first few months often the issue

12

Anti-epileptics and pregnancy?

Harm in first trimester
-Phenytoin
craniofacial abnormalities
hypoplasia of distal phalanges
growth deficiency
mental deficiency
-Valproate
associated with neural tube defects (spinal cord not closing)
-Carbamazepine
similar to phenytoin but decreased risk

Continuation of treatment is preferable - counselling
Or planned discontinuation
Carbamazepine was preferred
5mg folic acid given to reduce chances of neural tube defect

Lamotrigine used first line in generalised tonic-clonic seizures to avoid teratogenic / interacting drugs.
Hormones of pregnancy reduce its levels

13

anti-hypertensives and pregnancy?

ACE-I are not allowed, use beta-blockers instead or calcium-channel blockers, or methyl-dopa

14

Anti-coagulants and pregnancy?

Warfarin: teratogenics, particularly in semester 1 & 3
Use a LMWH instead!!

15

Do you use LFT as a guidance for hepatic impairment?

No, they are far less quantitative. Not like with GFR

16

Why should you be concerned with hepatic disease?

Considerations:
Hepatic clearance
Protein binding: they transport drug around body
Sodium retention: ascites, avoid sodium retaining drugs
Effects on coagulation (INR may be increased): the liver produces coagulation factors, therefore avoid warfarin
Gastric effects: NSAIDs avoid
CNS effects
Sedation