Pharmacology Flashcards
Why aren’t thrombolytics used more regularly?
Because they are associated with increased bleeding risk; the benefits do not always outweigh the harms.
Thrombolytics mechanism
- Catalyses activation of plasminogen into plasmin
- Plasmin breaks down fibrin in clots, thus dissolving them
What are the two main thrombolytic drugs?
- Tenecteplase
- Alteplase
List some conditions which beta blockers can be used to treat
- Heart failure
- Ischaemic heart disease
- Tachycardia
- Essential tremor
Which beta receptors do selective/non-selective beta blockers
Selective: Only block beta 1
Non-selective: Block beta 1 and beta 2
List two beta 1 selective beta blockers
- Atenolol, metoprolol (general)
- Nebivolol and bisoprolol (chronic systolic heart failure)
List four beta 1 selective beta blockers
- Atenolol, metoprolol (general)
- Nebivolol and bisoprolol (chronic systolic heart failure)
List three non-selective beta blockers
- Propanolol (chronic liver disease)
- Carvedilol (chronic heart failure)
- Labetalol (used in hypertension in pregnancy)
Absolute contraindications for beta blockers (think about all effects of beta receptors)
- Hypotension
- Uncontrolled heart failure
- Severe or poorly controlled reversible airways disease
Relative contraindications for beta blockers
- Diabetes (won’t be able to detect hypoglycaemia)
- Peripheral vascular disease (walking distance reduced)
Things to communicate when starting beta blockers
- Dizziness/tiredness
- Do not stop treatment suddenly
For what conditions are calcium channel blockers used?
- Hypertension
- Ischaemic heart disease
- Tachycardia
Effect of calcium channel blockers on vascular smooth muscle
Relaxation
Effect of calcium channel blockers on myocardium
Reduced contractility
Effect of calcium channel blockers on cardiac conduction tissue
Reduced heart rate
Effect of calcium channel blockers on gut
Relaxation of lower oesophagus (reflux) and intestine (constipation)
What are verapamil calcium channel blockers selective for?
Myocardium compared to peripheral vascular tissue
What are dihydropyridine calcium channel blockers selective for?
Peripheral vascular tissue
Which patients should not be prescribed DHP calcium blockers?
- Low HR
- Low BP
- Cardiac conduction defect
- Systolic heart failure
Dihydropyridines (CCB) adverse effects
- Vasodilation: flushing, headache
- Swelling of ankles
How do nitrates work? How do they make it easier for the heart to circulate blood around the body?
- Source of NO
- Relaxes smooth muscle structures such as veins and arterioles
- Reduced venous return, reducing preload and work
- Also, arteriolar dilation, lowering blood pressure and decreasing afterload
Ace Inhibitor suffix
-pril
Side effects of ACE inhibitors?
- Renal failure
- Bradykinin cough
- Rarely, angioedema
Why aren’t ARBs used all the time instead of ACE inhibitors? After all, they bypass the risk of bradykinin cough…
They aren’t as proven in some situations, and so ACEIs are usually used in the first instance.