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Flashcards in DRUGS Deck (35):

Oxygen: Description and MoA

Used for patients in hypoxemic states or at risk. Increases O2 sats and tissue perfusion- prevent anaerobic metabolism.
Useful in anxiety and stress.


Oxygen: Indications

1. Hypoxia: patients that are SOB or in a state of hypoperfusion
2. Accelerates reabsorption of pleural gas in pneumothorax
3. Reduce half life of carboxyhemoglobin in CO poisoning


Oxygen: Adverse Effects and interactions

- Can cause dry throat and mouth
**Less likely to occur with patient using nasal cannula (always consider in long term).
V flammable (smokers)


Oxygen: COPD patients

Physiologically respiratory drive is hypercapnia. In COPD flips to hypoxic drive so giving oxygen can depress RR and worsen hypoxia.
If it is an emergency COPD will still need oxygen.


Oxygen: Route

High flow (15L/min) through non rebreathe mask.
Can be given with reservoir of salbutamol
Venturi valves useful for controlling how much oxygen someone is receiving (good for COPD patients) - they blend oxygen with room air in fixed ratio


Oxygen: Prescribing and Dose

Often prescribed retrospectively. In emergency aim for sats 94-98 or 88-92 in COPD
HIGH FLOW: 15L/min (60-80% O2)
NASAL CANNULAE 2-6L/min (25-50%)


Corticosteroids (systemic): Examples

Prednisolone, Hydrocortisone, Dexamethasone


Corticosteroids (systemic): Indications

- Allergies or inflammation
- Autoimmune suppression
- Part of chemotherapy
- Hormone replacement for those with adrenal insufficiency


Corticosteroids (systemic): MoA

Bind to glucocorticoid receptors which then translate to cell nucleus and regulate gene expression. Up-regulate anti-inflammatory genes.
Suppress action of monocytes and eosinophils


Corticosteroids (systemic): Adverse effects

- Immunosuppression
- Muscle weakness, skin thinning and easy bruising


Corticosteroids (systemic): Dose

Prednisolone 5mg = Hydrocortisone 20mg

Prednisolone max dose 40-60mg


Short-acting Beta-2 agonists (Salbutamol): Indications

- Asthma reliever, PRN inhaler
- SOB relief in COPD
- Alongside insulin,glucose and calcium gluconate as urgent treatment for hyperkalaemia


Short-acting Beta-2 agonists (Salbutamol): MoA

- Beta-2 receptors found in tubes of body (on SMCs). GPCR which when activated leads to smooth muscle relaxation: dilate bronchioles
- Stimulate Na+/K+ ATPase pumps on cell surfaces pumping K+ into cellular compartment (hence good in hyperkalaemia)


Short-acting Beta-2 agonists (Salbutamol): Adverse effects

- Tachycardia, palpitations, anxiety and fine tremor (due to effect on heart and blood vessels)
- Increase serum glucose concentration (difficult for diabetics)
- Can lead to a rise in lactate levels leading to muscle cramps


Short-acting Beta-2 agonists (Salbutamol): Dose

- 100-200mg inhaled PRN no more than 4 times a day
- 2.5mg can also be nebulised


Long-Acting Beta-2 agonists (Salmeterol): MoA

Acts on Beta-2 GPCRs on SMCs to dilate bronchioles and improve ventilation. Also act on Na+/K+ ATPase pumps and move potassium into intracellular compartment: good for treatment for hyperkalaemia


Long-Acting Beta-2 agonists (Salmeterol): Indications

1. Asthma (usually 3rd line) after, and in combination with salbutamol and inhaled corticosteroids (beclametasone)
2. COPD second line therapy after steroids
3. Hyperkalaemia


Long-Acting Beta-2 agonists (Salmeterol): Adverse effects and interactions

Tachycardia, Palpitations, Tremor, anxiety, muscle cramps
Increased blood glucose.
Always give at same time as inhaled corticosteroids


Long-Acting Beta-2 agonists (Salmeterol): Route



Long-Acting Beta-2 agonists (Salmeterol): Dose and Prescribing

Combined inhaler with corticosteroids
Either as metered dose inhaler or dry powder inhaler


Anti-Cholinergics: MoA

Block the NT ACh - responsible for PARASYMPATHETIC control in the body including smooth muscle in the lungs.


Anti-Cholinergics: Anti-muscarinics

type of anti-cholinergic. Reduce smooth muscle tone and reduce secretions in the resp tract helping to relieve symptoms


Anti-Cholinergics: Examples

Ipratropium, Tiotropium


Anti-Cholinergics: Indications

1. COPD - help to relieve symptoms of exacerbations
2. Asthma. Can be added onto beta agonist or corticosteroid therapies


Anti-Cholinergics: Adverse effects and interactions

Often don't get into systemic circulation (inhaled) and so don't have that many adverse effects.
Dry mouth

Use with caution in ANGULAR GLAUCOMA because they can increase IOP


Anti-Cholinergics: Route, Prescribing and Dose

PRN or QDS standard dose is 40mg


Mucolytics: Examples



Mucolytics: MoA

Work by reducing the viscosity of the mucus which allows the patient to bring up their sputum much more easily.
This is important because if mucus lingers then this is a risk factor for developing a infection in the chest


Mucolytics: Indications

Useful for those that have productive coughs and might otherwise be a bit less able to clear their chests
- The frail

Also useful in patients with CF who have unusually thick and sticks mucus


Mucolytics: Adverse effects and interactions

Should not be given in patients who are on any medications to dry up their sputum or patients on ANTITUSSIVES

Also don't give to someone with a peptic ulcer because it can cause gastric bleeding


Mucolytics: Route, Prescribing and Dose

PO often chewable tablets. Can also be aerosolised
500mg PO chew


Theophylline: MoA

Useful for COPD management. Phosphodiesterase inhibitor which increases intra-cellular cAMP and inhibits leukotriene synthesis which reduced inflammation in bronchioles

Naturally occurring substance which is structurally similar to caffeine


Theophylline: Indications

1. COPD and asthmatics to help reduce inflammation in bronchioles (they also seem to increase steroid sensitivity)
2. Theophylline is a positive IONOTROPE (increases contractility of the heart)so can be useful in heart failure
3. Increases blood pressure and renal perfusion


Theophylline: Adverse Effects and interactions

Theophylline has narrow therapeutic window:
toxicity is increased by some antibiotics including erythromycin and flouroquinolones such as ciprofloxacin

- Nausea
- Diarrhoea
- Tachycardia


Theophylline: Route, Prescribing and Dose

For asthma: 250-500mg BD PO