Resp Drugs Flashcards
Prednisolone, Dexamethasone, Hydrocortisone
CORTICOSTEROIDS: these substances are good anti-inflammatories - they work by binding to glucocorticoid receptors on cells and forming a complex which is then translocated into the nucleus where it influences gene expression: Up-regulates anti-inflammatory markers and down regulates pro-inflammatory markers. Corticosteroids also have a inhibitory effect on monocytes and eosinophils hence enhancing their anti-inflammatory effects.
IND: Inflammatory conditions
Control of autoimmune conditions
Part of chemotherapy for cancer
To replace endogenous steroids when their is a secretory failure (e.g. hypopituitarism)
AE: CUSHING’S SYNDROME, thin skin, thin hair, says bruising, buffalo hump, round moon face
DOSE: Pred: 5mg/kg <60mg. 5mg pred is equivalent to 20mg hydrocortisone
Salbutamol
SHORT-ACTING BETA 2 AGONIST: Beta-2 receptors are found on the tubes of the body - vessels and bronchioles. Salbutamol agonises these receptors and caused dilation of the bronchioles helping to ease the symptoms of asthma - they act quickly and so are used for symptoms relief. They also activate the Na+/K+ ATPase channels on cells and lead to movement of K+ ions into the intra-cellular compartment - they are hence used as treatment for hyperkalaemia (with glucose, insulin and calcium gluconate)
IND: asthma symptomatic relief, COPD symptomatic relief and hyperkalaemia (part of combined therapy)
AE: They do have some effect on beta-1 and cause: tachycardia, palpitations, tremor and anxiety.
Can also cause an up regulation of glycogenolysis and hence lead to increase in blood sugar.
DOSE: 100-200mg inhaled or 2.5mg nebuliser
Salmeterol
LONG-ACTING BETA 2 AGONIST: Beta-2 receptors are found on the tubes of the body - vessels and bronchioles. Salbutamol agonises these receptors and caused dilation of the bronchioles helping to ease the symptoms of asthma - they act quickly and so are used for symptoms relief. They also activate the Na+/K+ ATPase channels on cells and lead to movement of K+ ions into the intra-cellular compartment - they are hence used as treatment for hyperkalaemia (with glucose, insulin and calcium gluconate)
IND: Asthma (third line after SABA and steroid) must be given with steroid otherwise there is increased risk of asthma death
COPD symptomatic relief
Hyperkalaemia
AE: They do have some effect on beta-1 and cause: tachycardia, palpitations, tremor and anxiety.
Can also cause an up regulation of glycogenolysis and hence lead to increase in blood sugar.
DOSE: Given as a combined inhaler with beclametasone because they must be given together
Ipratropium, Tiotropium
ANTI-CHOLINERGICS/ANTI-MUSCARINICS - these are examples of anti-muscarinics which are a sub-section of anticholinergics. They work by blocking the parasympathetic neurotransmitter ACh and hence increase heart rate and cause dilation of the bronchioles helping to ease symptoms of breathlessness. They also reduce the amount of respiratory secretions which makes the airways more clear and helps to ease respiratory symptoms
IND: asthma (SAMAs can be added to SABAs and LAMAs can be added to corticosteroid therapy)
AE: very few AEs because they don’t get into the systemic circulation. Dry mouth is a common complaint. DO NOT GIVE in people with, or at risk from acute angle closure glaucoma because they increase the intraocular pressure
DOSE: 40mg QDS given as inhaler
Carbocysteine
Carbocystein is an ANTI-MUCOLYTIC that works by breaking up di-sulphide bonds in mucus and hence making it less viscous. This means the patient it more able to bring the mucus up from their chest. If mucus stays around for too long it can be a risk factor for developing infection
IND: particularly useful in COPD for preventing acute exacerbations - especially in people who are frail and are less able to cough up their mucus
AE: Should not be used in people who are being view medication to suppress coughs (ANTITUSSIVES) also do not give to someone who has a history of gastric ulcers because it can cause haemorrhage
DOSE: 500mg PO or can be chewable
Theophylline
Theophylline is an anti-inflammatory that works by increasing cAMP pathways and hence preventing the production leukotrienes which prevents inflammation. Very similar to caffeine and some theophylline is produced in the metabolism of caffeine.
IND: asthma and COPD patients to decrease bronchiole inflammation
Is also a POSITIVE INOTROPE so can be useful in heart failure
Also increases blood pressure and hence renal perfusion
AE: Has a very therapeutic index and can be toxic if the dose is wrong. Some abx such as erythromycin and ciprofloxacin also make it more likely to be toxic.
Nausea, diarrhoea, tachycardia
DOSE: PO tablets 250-500mg every 12 hours
