PSA Flashcards
Name and example of a drug that is commonly presribed under the brand name and why?
tacrolimus
Becuause different forms micht alter concentration and affect toxicity/
What are common Enzyme inducers?
PC BRAS
P henytoin
Carbamazepine
B arbiturates
R ifampicin
A lcohol (chronic excess)
S ulphonylureas
Induce enzyme therefore reduce concentration of drugs
What are common Enyzme inhibitors?
AODEVICES
A llopurinol
O meprazole
D isulfiram
E rythromycin
V alproate
I soniazid
C iprofloxacin
E thanol (acute intoxication)
S ulphonamides
Increase drug concentration
When should you avoid metoclopramide?
Is a dopamine antagonist
- Patient with Parkinson’s
- Young women due to risk of dyskinesia
What is a good first-line prescription for anti-emetic? When should it be avoided?
Cyclizine 50mg 8hrl (IM/ IV oral)
–> avoided in cardiac cases as it might cause fluid-retention (metaclopromide 10mg (hrl) is safer)
What is the maximum dose of paracetamol per day?
1g 6-hourly (4g) for adults
But
if < 50 kg: 500mg 6-hourly (2g)
What are the main causes of thrombocytopenia?
- Reduced production
- Infection
- Drugs (especially penicillamine (e.g. for RA))
- myelodysplasia, myelofibrosis
- Increased destruction
- Heparin
- hyperspenism
- DIC + ITP
- HHS/ HUS
How can you biochemically differentiate between prerenal, intrinsic renal and postrenal AKIs?
Urea: creatinine rations migh be different
Pre-renal Urea»_space; creatinine
Intrinsic renal Urea «_space;creatinine no palpable bladder
Post-renal Urea«_space;creatinine with clinical signs of obstruction
Which drugs can commonly cause cholestasis?
Bilirubin with increase in ALP
Flucloxacillin
Co-amixiclav
nitrofurantoin
steroids
sulphonylureas
Which drugs can commonly cause hepatitis?
Paracetamol overdose
statins
rifampicin
If in a drug with monitored theapeutic window adequate response with high serum drug level is achieved, how should the drug administration be changed?
Name one example
Usually omitting the dose for a few days
Exept: gentamicin: reduce frequency of admission by 12h (e.g. change from 24h to 36h)
When should gentamicin blood levels be taken? What do they show?
2 samples
- Peak (1h post dose) - adjust dose if out of range
- Through (just before next dose) (adjust dose if out of range
Otherwise monitoring sample time will be at particular times 6-14h after infusion started (use graph to determine frequency of administration)
What are definitions for a major bleed?
- Causing hypotension
- Bleeding into a confined space (brain or eye)
What is the emergency management for a major bleed on warfarin?
Stop warfarin
give 5-10mg Vitamin K IV
give prothrombin complex
What should be done in patients on warfarin with increased INR but no bleeding
INR 5-8 omit warfarin for 2 days then reduce dose
INR >8 omit warfarin and give 1-5mg PO Vitamin K
What should be done for patients with increased INR and minor bleeding
INR >5: omit warfarina nd give 1-5mg Vitamin K
Which drug classes commonly cause SIADH?
sulfonylureas (e.g. Glimepiride)
SSRIs, tricyclics
carbamazepine
vincristine
cyclophosphamide
Which diuretics have to be avoided with Lithium? Why?
Should avoid ACEi and diuretics, in particular thiazide (because can reduce lithium excretion)
If diuretics are prescribed: aim for loop diuretics
What dietary modifications should be done in patiets taking statins?
Patients should avoid Grapefruits and Grapefruit juice due to risk of statin toxicity (due to inhibition of CYP3A4
–> Also not taken in conjunction with other enzyme inhibitors (e.g. clarithromycin - statins should be stopped)
How does active liver disease influence the use of statins?
Statins should be avoided in patients with active liver disease due to risk of change in metabolism
What drugs have severe interactions with Methotrexate and should be avoided?
Other folate antagonists, in particular
- trimethoprim and
- co-trimoxazole
Due to riks of bone marrow supression and neutropenic sepsis
What monitoring is required with Olanzapine?
- ECG (before and shortly after 1w initiation of treatnment for long-QT syndrome)
- Lipids and BP and weight every 3 months for first year, then annually
How are tacrolimus usually monitored?
With the through level (before morning or evening dose) –> aim for 6-10ng/mL
How should alcohol withdrawal with delirium be treated?
If signs of delirium tremens: Lorazepam or Diazepam (oral first, then IV)
Then ADD an antipsychotic if not improving
(The rest would be e.g. adding phenylbarbitone etc. but should only be considered if no improvement and secondary care involvement is started)
What is the treatment for alcohol withdrawal seizure?
Give intravenous lorazepam as a single dose. Give a second dose after 10 minutes if seizures continue. Always follow your local protocol.
What is the managment of patients with alcohol withdrawal without signs of delirium/ hepatic imparment etc?
chlordiazepoxide (long-acting benzodiazepine) (20mg PO 6hrl)
+ supportive care (aka glucose + thiamine, correct electrolyte imbalances)
What should often be communicated when prescribin rivaroxaban?
Doses of 15-20mg should be taken with food - otherwise risk of ineffectiveness
What is the treatment target when starting statins?
A reduction of >40% in non-HDL cholesterol
What are the most common drugs to cause confusion in the elderly?
Benzodiazepines
Anticholinergics (e.g. oxybutinin)
Drugs to treat insomnia
Steroids
Opioids
(Sedating) antihistamines
Be careful with
SSRIs/ antidepressants
Which drugs should be witheld in a patient with AKI due to risk of exacerbating the AKI?
- Contrast media
- ACE Inhibitor
- NSAIDs
- Diuretics (only some, can consider continuing loop diuretics e.g.)
- Angiotensin receptor blocker
Which common drugs are renally excreted and might therefore be stopped or reduced during an AKI?
- Opioids
- Aciclovir and many Antibiotics
- Allopurinol
- Lithium
- Colchicine
- Methotrexate
- Metformin if eGFR < 30
- Phenytoin, Gapapentin+ Pregabalin, Leviteracetam
https://www.thinkkidneys.nhs.uk/aki/wp-content/uploads/sites/2/2016/07/Medicines-optimisation-toolkit-for-AKI-MAY17.pdf
Which medication should be stopped in a patient undergoing routine contrast-CT studies?
Metformin (also ensure adequate hydration to prevent AKI)
f a patient at high risk for contrast-induced AKI (CI-AKI) is taking a metformin-containing medication, it should be discontinued for a minimum of 48 hours after the procedure and, if AKI develops, not reinstated until the kidney function has improved
How is serum osmolality calculated?
Serum osmolality is 2 x(Na) + Urea + glucose
(Normal Range 275 to 295)
How is anion gap calculated?
What is a normal range?
(Na+ + K+) – (Cl- + HCO3-) = Anion Gap
NR: 4 to 12 (16) mmol/L
What is usually the choice of antibiotic for serious MRSA infections?
Vancomycin
(can be others aswell, but usually they are a bit overkill)
Name some non-sedating antihistamines
loratadine or cetirizine
Which drugs can precipitate and acoute gout attack?
- Diureics, in particular Thiazide + loop diuretics
- Low-dose aspirin
- Ticagrelor
- calcineurin inhibitors (e.g. tacrolimus)
- pyrazinamide