PRESCRIBING Flashcards
(24 cards)
What does an enzyme inducer do to the P450 system?
Increase activity of P450 resulting in a reduced effect
Examples of enzyme inducers
PC BRASS
Phenytoin
Carbamezapine
Barbituates
Rifampacin
Alcohol (chronic excess)
Sulphonylureas
What does an enzyme inhibitor do to P450 system?
Decrease the P450 system which will lead to increased levels of other drugs
Examples of enzyme inhibitors
AODEVICES
Allopurinol
Omeprazole
Disulfram
Erythromycin
Valproate
Isoniazid
Ciprofloxacin
Ethanol (acute intoxication)
Sulphonamides
How do you prescribe topical drugs?
Fingertip units (FTU)
Which drugs should be stopped before surgery?
I LACK OP:
Insulin
Lithium
Anticoagulants/antiplatelets
COCP/HRT
K- sparing diuretics
Oral hypoglycaemic
Perindopril and other ACE-i
When do you stop the COCP or HRT before surgery?
4 weeks before
When do you stop lithium before surgery?
1 day before
When do you stop K+ sparing diuretics and ACEi before surgery?
The day of surgery
When do you stop anticoagulation before surgery?
Variable - occasionally continued
When do you stop oral hypoglycaemic and insulin before surgery>
Variable - if patients are NBM metformin should be stopped as it causes hypoglycaemia
Prescribing (ACCURATE)
Allergies
Correct patient
Contraindications
Units
Route (vomit, swallow, NBM)
Analgesia, anti-emetic
Thromboprophylaxis
End of date of course
Replacement fluids
0.9% saline
if hypoglycaemic or hypernatraemia then 5% dextrose
Maintenance fluids
25-30ml/kg/24h water
1mmol/kg/24h Na+ and K+
50-100g/24h glucose
1l over 8-12h
Fluid losses
NaCl 0.9% and K 0.3% (40mmol)
1l over 4-6h
Hypoglycaemia fluid replacement
Glucose 20%
100ml over 15 mins
Resuscitation (low BP and high HR) fluid
NaCl 0.9%
500ml over 15 mins or less
Hypokalaemia fluid replacement
Max 10mmol/h
NaCl 0.9% and K 0.3% (40mmol)
1l over 4h
Hypercalcaemia fluid replacement
NaCl 0.9%
1l over 4h
Fluid resus in children
10ml/kg
NaCl 0.9%
100ml/kg/24h for first 10kg
50ml/kg/24h for next 10kg
20ml/kg/24h for anything after
What drugs can you use for DVT?
Dalteparin
Enoxaparin
When is the best time of day to prescribe an ACE-i?
Evening as they can cause postural hypertension
What do you give in acute asthma?
Salbutamol nebulisers
What fluid do you give in DKA?
50 units of ActRapid with 0.9% saline via IV
