prescription review Flashcards
safe routine for prescribing
PReSCRIBER:
* Patient details
* Reaction (i.e. allergy plus the reaction)
* Sign the front of the chart
* check for Contraindications to each drug
* check Route for each drug
* prescribe Intravenous fluids if needed
* prescribe Blood clot prophylaxis if needed
* prescribe antiEmetic if needed and
* prescribe pain Relief if needed.
Patient details required
patient name, DOB and CHI
drugs that contain penicillin (not obvious from name)
Tazocin and co-amoxiclav
CI for antiplatelets and anticoagulants
Drugs that increase bleeding (e.g. anti-platelets and anti-coagulants) should not be given to patients who are bleeding, suspected of bleeding, or at risk of bleeding (e.g. those with a prolonged prothrombin time due to liver disease). Do not forget that prophylactic heparin is generally not appropriate in acute ischaemic stroke due to the risk of bleeding into the stroke. It is also important to remember that an enzyme inhibitor (such as erythromycin) can increase warfarin’s effect (and thus the prothrombin time (PT) and international normalized ratio (INR)) despite a stable dose. This should be considered when patients present with excessive anticoagulation.
CI steroids
For steroids, remember the side effects (and thus, more loosely, the contraindications) by using the mnemonic STEROIDS:
* Stomach ulcers
* Thin skin
* oEdema
* Right and left heart failure
* Osteoporosis
* Infection (including Candida)
* Diabetes (commonly causes hyperglycaemia and uncommonly progresses to diabetes)
* Cushing’s Syndrome.
NSAIDs CI
With non-steroidal anti-inflammatory drugs (NSAIDs), the following safety considerations may be remembered with the mnemonic NSAID:
* No urine (i.e. renal failure)
* Systolic dysfunction (i.e. heart failure)
* Asthma
* Indigestion (any cause),
* Dyscrasia (clotting abnormality).
antihypertensives CI
For antihypertensives, always think of the side effects in three categories:
a. Hypotension (including the earliest symptom, postural hypotension) that may result from all groups of antihypertensives.
b. Dividing the groups of antihypertensives into two mechanistic categories:
1. Bradycardia may occur with beta-blockers and some calcium-channel blockers.
2. Electrolyte disturbance can occur with angiotensin converting enzyme (ACE)-inhibitors and diuretics (see Chapter 3).
c. Individual drug classes have specific side effects:
1. ACE-inhibitors can result in a dry cough.
2. Beta-blockers can cause wheeze in asthmatics; they can also cause worsening of acute heart failure (but help chronic heart failure).
3. Calcium-channel blockers can cause peripheral oedema and flushing.
4. Diuretics can cause renal failure. Thiazide diuretics (e.g. bendroflumethiazide) can also cause gout, and potassium-sparing diuretics (e.g. spironolactone) can also cause gynaecomastia.
antiemetic dose oral -> IV conversion
Conveniently, the doses of the common antiemetics are the same regardless of the route taken, e.g. cyclizine 50 mg 8 hourly, metoclopramide 10 mg 8 hourly.
For replacement fluids, when should you not give 0.9% saline
the patient:
* Is hypernatraemic or hypoglycaemic: give 5% dextrose instead.
* Has ascites: give human-albumin solution (HAS) instead. The albumin maintains oncotic pressure; furthermore, the higher sodium content of 0.9% saline will worsen ascites.
* Is shocked from bleeding: give blood transfusion, but a crystalloid first if no blood available.
maintenance fluid requirement in adults and elderly
As a general rule, adults require 3 L IV fluid per 24 hours and the elderly require 2 L.
giving adequate electrolytes
Adequate electrolytes are provided by 1 L of 0.9% saline and 2 L of 5% dextrose (1 salty and 2 sweet).
giving potassium suplementation
To provide potassium, bags of 5% dextrose or 0.9% saline containing potassium chloride (KCl) can be used but this should be guided by urea and electrolyte (U&E) results; with a normal potassium level, patients require roughly 40 mmol KCl per day (so put 20 mmol KCl in two bags).
when to avoid thee antiemetic metocloperamide?
metocloperamide is a dopamine antagonist and it should be avoided in:
* Patients with Parkinson’s disease, due to the risk of exacerbating symptoms.
* Young women, due to the risk of dyskinesia, i.e. unwanted movements especially acute dystonia.
when is cyclizine not used as a antiemetic?
Note: cyclizine is a good first-line treatment for almost all cases except cardiac cases (as it can worsen fluid retention), where metoclopramide 10 mg 8 hourly IM/IV/oral is safer.
neuropathic pain
he first line treatment is amitriptyline (10 mg oral nightly) or pregabalin (75 mg oral 12 hourly); duloxetine (60 mg oral daily) is indicated in painful diabetic neuropathy.
Duloxetine = D for Diabetes
