Pharmacology Flashcards
What antibiotic would you prescribe for a patient with hospital acquired pneumonia that has a mild allergy (rash) to penicillin?
Cephlasporins such as Cefuroxime
What antibiotic would you prescribe for a patient with hospital acquired pneumonia that has a severe allergy (anaphylaxis) to penicillin?
Vancomycin plus ciprofloxacin
Drugs used for hypertension? (AABCD)
Angiotensin Converting Enzyme inhibitors Angiotensin Receptor Antagonists Beta-Blockers Calcium Channel Blockers Diuretics
What is the function of angiotensin II? (3 things)
Increase thirst Vasoconstriction Increased aldosterone (increases Na reabsorption)
If a drug ends in the name pril what is it likely to be? (any examples?)
A ACE inhibitor
Catapril, ramipril
Side effects of ACE inhibitor
Sudden drop in BP (should level out though)
Can cause a dry cough in people (increase bradykinin)
Which drugs end in sartan?
Angiotensin Receptor Antagonists (Candesartan/losartan)
How do Beta blockers reduce BP?
They cause vasodilation and reduce cardiac output. Also can reduce renin = reduce aldosterone
Give some examples of B-blockers?
Propanolol
atenolol - cardioselective
Pindolol
What are the 2 different types of CCB? And what is the difference between them?
Dihydropyridines - block voltage gated sodium channels –> vasodilation –> reduced resistance and therefore BP
Non-dihydropyridines - these also dilate arteries however are rate limiting therefore dont cause reflex tachycardia as also slow the HR
Nifedipine and amlodipine are examples of what type of drug?
CCB’s - dihydropyridine
verapamil and Diltiazem are examples of what type of drug?
CCB’s - Non-dihydropyridine
What are the possible uses of β-blockers?
Antiarrhythmics
Secondary prevention of MI and in reducing angina symptoms
Anti-hypertensive
Glaucoma treatment (reduce the aqueous secretion)
Anxiety treatment - reduce HR and limit SNS activation
How do β-blockers work and where do they work?
Reduces cardiac contractility and suppresses the cardiac pacemakers (particularly the AV node) to reduce the HR. As well as reducing renin secretion in the kidney. Impair gluconeogenesis and reduce the secretion of insulin.
What are the 3 types of β receptors/ where are they found ?
1 - mainly in the heart
2 - Heart + bronchial and peripheral vascular smooth muscle
3 - Heart and adipose tissue
Where and by what are β-blockers metabolised by?
Metabolised in the liver by CYP450 enzyme
What is the first line treatment for AF?
- What makes it suitable?
Beta blockers
- Rate limiting and reduction of contractility
Which β-blockers are cardioselective?
atenolol/metoprolol
What is the mechanism of action of fenofibrate?
activates PPAR-alpha which upregulates HDL secretion and decreases apolipoprotein synthesis in the liver.
Penicillin can cause AKI - what is the mechanism of action for this reaction?
Acute interstitial nephritis
What effect does angiotensin 2 have on the efferent and afferent arterioles of the kidney?
Vasoconstricts the efferent arteriole - increasing filtration
What is first line treatment for acute gout?
NSAIDs
What anticoagulant is most likely to cause bruising?
Warfarin - older style and has a narrow therapeutic range which can be altered by small factors such as increased green vegetables
What 5 medications are known to be ototoxic?
- and what is ototoxicity?
Ototoxicity = long standing damage to the ear which can lead to hearing loss and tinnitus . LAAQC Loop diruetics Aspirin aminoglycoside antibiotics - mycin's Quinine cisplatin and chemotherapy meds
Drugs ending with prazole are what type of drugs?
Proton pump inhibitors
What is the mechanism of action for PPIs and possible side effect?
Irreversibly block the proton pump of the parietal cells in the stomach. Work very well blocking 90% therefore pH can rise and cause bacteria to grow. Can mask gastric cancer so want to be checking.
You want to put a patient on a PPI for the GORD however they are also taking warfarin therefore which PPI would be best to be used and why?
Lansoprazole - not metabolised by CYP450 like omeprazole/pantoprazole. Instead is metabolised by CYP450 B. Therefore doesn’t affect the metabolization of warfarin.
How often do PPIs need to be taken?
1 a day as they irreversibly bind therefore 1 dose lasts 24 hours as the pump needs to be resynthesised.
What are the 3 mechanisms of action for statins?
- reduce the amount of HMG CoA reductase = reducing the production of acetyl coA to cholesterol in the liver
- Increase the amount of LDL receptors = more LDL brought back to the liver and reused instead of becoming atheromas.
- Increase HDL levels.
What are the other positives of statin in terms of reducing LDL levels?
Reduces inflammation and reduced risk of some cancers (prostate and colorectal)
What are the main 2 possible side effects of statins?
Rhabdomyolysis
Myalgia - 5%
Where is the vomiting centre and what receptors are present in it?
It is in the medulla oblongata and H1, NK1 and M1 receptors are present.
Where is the chemoreceptor trigger zone found and what receptors are present in it?
In the fourth ventricle
5-HT3, D2 and some NK1
What vomiting receptors are present in the gut?
5-HT3 and some D2
What type of drugs are Cyclizine, cinnarizine, promethazine? and what are they used for?
H1 receptor antagonists (anti-histamines) - nausea, vomiting, vertigo, motion sickness
Name examples of dopamine 2 receptor antagonists?
why is one better than the others?
Metoclopramide
Domperidone - doesn’t cross BBB so reduced S/E however can cause cardiac arrhythmias.
Prochlorperazine
What is ondansetron mechanism of action?
5-HT3 antagonist - CTZ and gut
Aprepitant is a example of what type of drug?
Neurokinin antagonists (NK1)
Through what nucleus does the gag reflex go through?
Nucleus solitarius
What can reverse the effects of warfarin? (2)
Vitamin K
Pro thrombin complex concentrate
What is used to reverse the effects of unfractionated heparin?
Protamine Sulphate
What is used to reverse the effects of dabigatran?
Idarucizumab
What is the first line treatment for focal epilepsy?
What is the second line treatment for focal epilepsy?
- Carbamazepine
2. Lamotrigine
What is the first line treatment for hypertension in a patient of african/caribbean descent or that are over 55?
A calcium channel blocker such as amlodipine. As ACEI and BB are less effective
Which type of medication can cause a prolongation of the QT interval?
Tricyclic medication such as amitriptyline
WHich blood pressure medication can increase the sensitivity to insulin putting diabetic patients at an increased risk of hypoglycaemia?
ACE inhibitors - Ramipril
What are pottential side effects of metformin?
GI disturbances - diarrhoea, nausea Lactic acidosis (only if have contraindications so need to do U+Es before)
What drug is used in a opioid overdose?
Naloxone
