PSA: monitoring drug therapy

Question 1

Baseline tests methotrexate

Answer 1

Baseline tests should include FBC, U&E, LFT, ESR and CRP.

Selected patients may require
pulmonary function testing and CXR.

Question 2

Drug monitoring methotrexate

Answer 2

FBC, U&E and LFT should be checked every 1-2 weeks until patient is stabilised and

then every 2-3 months thereafter (monthly in rheumatology).

ESR and CRP
should be re-checked every 3 months.

Question 3

what should you ask about at every appt regarding methotrexate SE

Answer 3

Also ask about oral ulceration/sore throat, unexplained rash or unusual bruising at every
consultation.

Question 3

what should you monitor hydroxycloriquine

Answer 3

bull’s eye retinopathy - may result in severe and permanent visual loss

Monitoring
baseline ophthalmological examination and annual screening is generally recommened
the BNF advises: ‘Ask patient about visual symptoms and monitor visual acuity annually using the standard reading chart’

Question 4

After a change in dose, how often should lithium levels be checked

Answer 4

after a change in dose, lithium levels should be taken a week later and weekly until the levels are stable.

Question 5

how many hours after a dose should lithium levels be checked

Answer 5

12 hours post dose

Question 6

Therapeutic range lithium

Answer 6

0.4-1.0 mmol/L

Question 7

When should thyroid and renal be checked when patients taking lithium

Answer 7

Every 6 months

Question 8

when lithium levels are stable, how often are they checked

Answer 8

Once stable, blood test 12 hours post-dose every 3 months

Question 9

baseline measurements therpaeutic monitoring lithium

Answer 9

renal: U&E, eGFR,

thyroid: free T4, TSH,

weight and height (plus FBC
and ECG if indicated).

Question 10

what should be checked every 3 months lithium

Answer 10

serum lithium level (normal therapeutic range 0.4-1.0mmol/l, set target
for each patient)

Question 11

what should be checked every 6 months lithium

Answer 11

thyroid and renal and BMI:

– fT4, TSH, U&E and eGFR

Question 12

what should be checked every 12 months lithium

Answer 12

check height and weight (BMI)

Question 13

how often do you monitor FBC in pts on clozapine

Answer 13

checking the FBC every week for the first 18 weeks, every second week up to 1 year, and then at monthly intervals.

Question 14

when should theophylline plasma concentration be measured after treatment is commenced

Answer 14

5 days after therapy is commenced

Question 15

how many hours after last dose should a theophylline plasma conc be taken

Answer 15

4-6 hours after the dose

Question 16

theophylline plasma conc req for therapeutic effect

Answer 16

10-20mg/litre

Question 17

drug monitoring amiodarone

Answer 17

Liver function tests required before treatment and then every 6 months.

Serum potassium concentration should be measured before treatment.

Chest x-ray required before treatment

Thyroid function tests should be performed before treatment, then at 6-monthly intervals, and for several months after stopping treatment (particularly in the elderly).

Question 18

drug monitoring sodium valproate

Answer 18

Monitor liver function before therapy and during first 6 months especially in patients most at risk.

Measure full blood count and ensure no undue potential for bleeding before starting and before surgery.

Question 19

what electrolyte disturbance increases risk of digoxin toxicity

Answer 19

hypokalameia

Question 20

what should you monitor digoxin

Answer 20

serum conc if iv?

U&Es (renal function poor can increase risk of toxicity. hypokalameia increases risk of arrythmia)

Question 21

drug monitoring statins

Answer 21

before treatment:
LIVER FUNCTION full lipid profile (non-fasting) and triglyceride concentrations, thyroid-stimulating hormone, and renal function should also be assessed.

During:
Liver function repeated within 3 months and at 12 months of starting treatment, unless indicated at other times by signs or symptoms suggestive of hepatotoxicity.

Question 22

should you check CK before initiating statins?

Answer 22

in patients who have had persistent, generalised, unexplained muscle pain (whether associated or not with previous lipid-regulating drugs);

if the baseline concentration is more than 5 times the upper limit of normal (ULN), a repeat measurement should be taken after 7 days.

If the repeat concentration remains above 5 times the ULN, statin treatment should not be started;

if concentrations are still raised but less than 5 times the ULN, the statin should be started at a lower dose.

Question 23

if want to initiate methotrexate but LFTs abnormal, what do you do?

Answer 23

dont initiate

risk of cirrhosis

Question 24

monitoring all antipsychotics

Answer 24

Prolactin concentration at the start of therapy, at 6 months, and then yearly

Physical health monitoring (including cardiovascular disease risk assessment) at least once per year

Question 25

drug monitoring olanzapine

Answer 25

Blood lipids and weight should be measured at baseline, every 3 months for the first year, then yearly.

Fasting blood glucose tested at baseline, after one months’ treatment, then every 4–6 months.