Chapter 2- Prescription Review Flashcards
Side effects and CI to steroids
Stomach ulcers Thin skin oEdema Right and left heart failure Osteoporosis Infection eg. Candida Diabetes Syndrome- Cushings
CI to drugs that increase bleeding eg.aspirin, heparin, warfarin, rivaroxaban
- active or suspected active bleeding
- risk of bleeding (prolonged PT eg. Liver disease)
- heparin CI in acute stroke: risk of heamorrhagic transformation
- enzyme inhibitors eg. Erythromycin increase warfarin effect (increase PT, INR)
3 categories of SE of anti HTN medications
- Those of all antiHTN– postural hypotensino
- Mechanistic SE:
B-blockers and rate limiting CCB –> Bradycardia
ACEi and Diuretics –> Electrolyte disturbances - Those specific to the drug classification
SE of ACEi (3)
- Dry cough (increased bradykinin as no ACE to metabolise it)
- Hyperkalaemia (Reduced aldosterone, therefore reduced excretion of K+)
- Acute renal failure (reduced ANGII so no efferent arteriole constriction if GFR reduces)
SE of B-blockers (3)
- Bradycardia
- Wheeze (brittle asthma)
- worsens acute heart failure (cf. Rx in chronic HF)
SE of CCBs (2)
- Peripheral oedema
2. flushing
SE of diuretics:
- All diuretics
- K sparing Diuretics
- Loop diuretics
- renal failure due to hypoperfusion of the kidney
- eg. frusemide: GOUT
- eg. Spironolactone: Gynaecomastia
Antihypertensives causing Hypokalaemia
Loop Diuretics: Frusemide
Thiazides:
Antihypertensives causing Hyperkalaemia
K sparing diuretics: Spironolactone
ACEi: Perindopril
ACEi- HTN
To be used in younger patients (<55years) with HTN (A)
Should not be used in Afro-caribbean pts (angioedema).
Highly indicated for HTN + DM nephropathy
Must stop K supps and K sparing diuretics before use.
ACEi- heart failure
Used in acute and chronic HF
Must stop K supps and K sparing diuretics before use.
In pts with HF who are on loop diuretics, can cause first dose hypotension. STOP loops to prevent this. BUT… increased risk of REBOUND PULMONARY OEDEMA.
Renal Effects of ACEi
- Check U&E, Cr before starting
- hyperK more common in renal impairment (and if on K sparing diuretics)
- NSAID + ACEi increases risk of renal damamge
- CI: bilateral RAS
Names of ACEi
Capatopril
Enalapril
Lisinopril
Perindopril
Names of ARBs
ANG II-R-ANT
Candesartan
Irbesartan
Fluid depletion- clincial examination –> approximation
500ml depletion = Oliguria (<30ml/hr or anuria)
1L depletion = OLiguria + tachicardia
2L depletion + Oliguria + shock
Fluid replacement in a tachycardic/hypotensive patient
500ml Bolus
1L if Young and fit
250ml if in heart failure
reassess
Fluid replacement in an oliguric (and non obstructed patient)
1L over 2-4 hours –> reassess.
Maintenance fluids of an adult (non elderly)
- total volume
- Prescription to give adequate electrolytes
- total volume = 3L/24hours –> 8 hourly bags
- 1L NaCl + 2L 5% Dexrose / 24 hours (if not eating)
- K+ supplementation: 40mmol/L/day –> 20mmol KCl in 2 bags of fluid.
- Plasmalyte- compound sodium acetate
- Hartmanns contains K and lactate
Signs of Fluid Overload
- raised JVP
- Peripheral oedema
- Pulmomary oedema
Blood Clot prophylaxis
LMWH and TED stockings
CI to LMWH
- bleeding or risk of bleeding
- recent ischaemic stroke (haemorrhagic transformation risk)
CI to TED stockings
peripheral arterial disease (absent foot pulses) –> risk of acute limb ischaemia (6Ps)
Antiemetics: mechanisms of action
H1-ANT: Cyclizine
DA2-ANT: Metoclopramide, Domperidone
DA-ANT: Phenothiazines- block chemo-R trigger zone: Prochlorperazine
5HT3-ANT: Ondansetron
Cyclizine
H1 ANT
Good first line anti emetic EXCEPT IN HEART FAILURE (SE: fluid retention)
50mg 8hourly (PO/IV/IM)
Metoclopramide
DA2-ANT
Can be used in heart failure 8hourly IV/IM
AVOID:
1. Parkinsons
2. Young Women –> acute dystonic reactions (oculogyric crisis)
Domperidone
DA2-ANT
CAN be used in PARKINSONS: doesnt cross BBB
Maximum daily dose Paracetamol
1g upto 6hourly (Max 4g in 24hours)
Maximum Codeine daily
30mg up to 6hourly (120mg in 24 hours)
Maximum Morphine daily
10mg up to 6hourly (40mg daily)
Caution in Oramorph: 10mg/5ml and 5mg/5ml
Analgesia in neuropathic pain
First line: Amitryptilline, PreGABAlin
Painful diabetic neuropathy: Duloxetine
Giving Methotrexate and Trimethoprim (or any other folate ANT) is CI becasue it can cause…..
PANCYTOPENIA
If a patient is on Methotrexate and develops sepsis….
STOP METHOTREXATE IMMEDIATELY until you have excluded neutropenic sepsis
breakthrough dose of opiates
1/6 of daily morphine dose.
eg. pts usual dose is 30mg BD, so break through dose is 1/6 of 60mg = 10mg
should also prescribe this when pt receiving opioids
laxative
Opioids in CKD…
Alfentanil
Buprenorphine
Fentanyl
preferred
Pain relief in metastatic bone pain
NSAIDS
Bisphosphonates
RT
Conversion from codeine to morphine
divide by 10
conversion from tramadol to oral morphine
divide by 10
