308 Respiratory pharmacology Flashcards
Name some Beta-2 agonist bronchodilators
Salbutamol
Salmeterol
Formoterol
Vilanterol
Name some muscarinic antagonists/anticholinergic br0nchodilators
Tiotropium (LAMA)
Name some LAMA’s
Tiotropium
Aclidinium
Glycopyrronium
Umeclidinium
Name a SAMA
Ipratropium
Name a methylxanthine bronchodilator
Aminophylline
Name some anti-inflammatory steroids used in the airway
Prednisolone (oral))
Beclomethasone (ICS)
What does ICS stand for?
Inhaled corticosteroid
What does LAMA stand for?
Long-acting muscarinic antagonist
What is a SAMA?
Short-acting muscarinic agonist
Name a leukotriene receptor antagonist
Montelukast
What are Mucolytic agents?
They reduce viscosity of drugs that makes them easier to cough up
Eg. Carbocysteine (tablet), hypertonic saline (via nebuliser)
How do you use a pressurised metered dose inhaler (pMDI)?
Deep exhale, inhale and puff
Hold breath for 10 seconds
Exhale slowly
Wait 1 minute before 2nd puff
What is Salbutamol?
A short acting bronchodilator (SABA) 3-5hrs duration
It’s inhaled or nebulised in higher doses, can be IV
Used in asthma and COPD
What is the mechanism of action of Salbutamol?
It binds to beta-2 receptors in the lungs causing relaxation of bronchial smooth muscle
Salbutamol increases cAMP production by activating adenylate cyclase
What is Salmeterol?
A long-acting bronchodilator (LABA)
Begins after 2-30 mins, lasts 10-12hrs
Always used with ICS
Inhaled
Used in asthma and COPD which remains persistent despite SABA
Which medications are combined to form Seretide?
Fluticasone (ICS) and salmeterol
What is Formoterol?
A long-acting LABA, 10-12hrs duration
Inhaled
Used in asthma and COPD
Always combined with a ICS for asthma
What is Tiotropium?
A long acting LAMA, 24hrs duration
Inhaled
Used in stable COPD which has symptoms despite SABA or in Asthma which isn’t improving despite ICS/LABA care
How does Tiotropium work?
A LAMA
Works on M3-receptors at the smooth muscle leading to bronchodilatation
Has a similar affinity for M1-M5 subtypes of receptors
What is Ipatropium?
A SAMA
Onset: 30min
Duration: 6 hours
Nebulised in acute presentations of COPD and sometimes asthma
What is theophylline?
Its a phosphodiesterase inhibitor
5hrs duration
Administered orally or IV
Used orally in COPD and asthma with persistent symptoms
Given IV in medical emergencies for COPD and Asthma
Why does Theophylline use require blood monitoring?
It’s to avoid toxicity
Consequences of theophylline intoxication include metabolic disturbances (hypokalemia, hyperglycemia, and metabolic acidosis), nausea, vomiting, and, in severe cases, seizures, cardiac arrhythmias, and death
What are the airway effects of glucocorticoids?
Decreases:
-Releases of inflammatory mediators
-Infiltration and action of WBC
-Airway oedema
-Airway mucus production
Increased number and sensitivity of beta-2 receptors
Name some systemic glucocorticoids
Prednisolone
Why are inhaled glucocorticoids preferred to systemic ones?
Because systemic ones have more side effects, especially with long-term therapy
Name some inhaled glucocorticoids
Beclomethasone
Fluticasone
Budesonide
Why might systemic glucocorticoids be chosen over inhaled ones?
Because the disease may prevent penetration of the drug to affected areas
What are some side effects of glucocorticoids?
Inhaled: oral candidiasis (white plaques in mouth and dysphonia
General:
-Adrenal suppression
-Bone loss
-Slow growth in children but doesn’t affect ultimate height
-Increased risk of cataracts and glaucoma
-Increased risk of infection
-Gastric ulceration
-Hypertension
-Diabetes
-Mood disturbance
What is dysphonia?
Disorders of the voice
Name some ICS/LABA combination inhalers
Formoterol/Budesonide
Formoterol/beclomethasone
Salmeterol/Fluticasone
Name some LAMA/LABA combination inhalers
Tiotropium/Olodaterol
Name some ICS/LABA/LAMA combination inhaler
Beclomethasone/formoterol/glycopyrronium
What are the steps for the asthma treatment ladder?
Step 1
-As needed low dose ICS (formoterol)
Step 2
-Daily low dose ICS and as -needed low dose ICS (formoterol)
Step 3
-Low dose ICS-LABA and as-needed ICS (formoterol)
Step 4
-Medium dose ICS-LABA and as-needed ICS (formoterol)
Step 5
-High dose ICS-LABA and as-needed ICS (formoterol)
-Refer to phenotypic assessment
What are the steps for inhalers with COPD?
- Offer SABA OR SAMA to use as needed
- If continues and patient has no features of asthma, offer LABA + LAMA. If symptoms still severe, offer 3 months trail of LAMA + LAMA + ICS
- If continues and patient has asthmatic features, consider LAMA + ICS
(LABA + LAMA + ICS is always the last option. if they don’t work, explore other forms of treatment)
What are the treatment options for allergic rhinitis?
-Antihistamines (H1 antagonists)
Eg, Cetirizine and chlorpheniramine
-Intranasal glucocorticoids
Eg, Beclomethasone (Beconase)
-Montelukast
Sympathomimetics (decongestants)
Eg, Pseudoephedrine (alpha-agonist)
(Problems with abuse)
How does Montelukust treat allergic rhinitis?
It inhibits leukotriene receptors
This reduces inflammation, bronchoconstriction, oedema, mucus, and recruitment of eosinophils
When can over oxygenation occur?
In type 2 respiratory failure
What is the difference between type 1 and type 2 respiratory failure?
Type 1 respiratory failure:
When the respiratory system cannot adequately provide oxygen to the body, leading to hypoxemia.
Type 2 respiratory failure:
When the respiratory system cannot sufficiently remove carbon dioxide from the body, leading to hypercapnia
What is the difference between bronchitis and pneumonia?
Bronchitis affects the bronchial tubes that carry air to your lungs
Pneumonia affects the alveoli, where oxygen passes into your blood
What are the different types of respiratory infection?
-Bronchitis (COPD and asthma)
-Community acquired pneumonia (CAP)
-Hospital acquired pneumonia (HAP)
-Ventilator acquired pneumonia (VAP)
-Aspiration pneumonia
Name some antibiotics used to treat respiratory infections
-Penicillin’s: Amoxicillin, Co-amoxiclav
-Tazobactam
-Tetracyclines: Doxycycline
-Quinolone: Ciprofloxacin, Levofloxacin, Moxifloxacin
-Macrolides: Erythromycin, Clarithromycin
When is amoxicillin used to treat respiratory infections?
-Community acquired pneumonia (typical)
-COPD exacerbations
-Bronchitis
Which type of bacteria does amoxicillin work against?
It’s a moderate-spectrum, bacteriolytic, Beta-lactam antibiotic
Active against gram negative and positive bacteria
What is Co-amoxiclav?
A combination of amoxicillin and clavulanic acid (a beta lactamase inhibitor) which prevents the antibiotic from being degraded by the bacteria
When is doxycycline prescribed to treat respiratory infections?
With atypical infections
Eg, mycoplasma and legionella
Oral route only
How does doxycycline work?
It inhibits protein synthesis
It’s and broad spectrum gram positive and negative antibiotic
What are the side effects of doxycycline?
GI upset
Staining teeth
Lupus
Allergy
Photosensitivity
How do Quinolone antibiotics work?
Eg, Ciprofloxacin, Levofloxacin, moxifloxacin
They cause DNA fragmentation
Which bacteria do Quinolones work on?
Gram negative and positive bacteria and pseudomonas
Which types of bacteria are macrolides used on?
Eg, erythromycin, clarithromycin
Used in atypical pneumonia
Work on gram positive bacteria, limited gram negative cover
What is the route of administration of macrolides?
IV or oral
What is the route of administration for Quinolones?
IV, oral, or inhaled
How do macrolides fight infection?
They are protein synthesis inhibitors
What are the side effects of Quinolones?
GI upset
C difficile
Tendonitis
Liver upset
Prolonged QTc and arrthymias
What are the side effects of Macrolides?
GI upset
Allergy
liver abnormality
prolonged QTc
Interactions
What is the treatment for Tuberculosis?
6 month treatment
First 2 months: Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol
After 2 months: Isoniazid and Rifampicin
When would the 6 month treatment period for TB be extended?
If there is central nervous system involvement the continuation phase of treatment is extended to 10 months making a 12 month full treatment plan
How is the TB treatment taken?
TB treatment is taken all together on an empty stomach 1 hour before breakfast; compliance is essential for cure
What are the side effects of TB therapy?
Isoniazid
-Bactericidal and bacteriostatic – inhibits cell wall growth
-Cytochrome P450 inhibitor – interactions!!
fever, peripheral neuropathy and optic neuritis
Rifampicin
-inhibits bacterial DNA-dependent RNA synthesis
-Cytochrome P450 inducer – interactions!!
reddish colour to the urine
Pyrazinamide
-Causes accumulation pf pyrazinoic acid
use with caution in patients with gout
Ethambutol
-Bacteriostatic obstructs development of cell wall
-Peripheral neuropathy, optic neuropathy , gout, AKI
General side effects: Hepatotoxcity, nausea and skin rashes, Allergy
Name some types of Interstitial lung disease (ILD)
Hypersensitivity pneuomina
Sarcoid
Idiopathic pulmonary fibrosis
What is cystic fibrosis?
Mutation of the CFTR gene
What are the different classes if CFTR mutation?
Protein production
Protein processing
Gating
Conduction
Insufficient protein
Name some CFTR modulating drugs
Kalydeco®(ivacaftor) Class 3 mutation . Increases channel opening probability of G551D CFTR
Orkambi®(lumacaftor/ivacaftor) CFTR corrector, Class II mutation + above
Symdeko®(tezacaftor/ivacaftor) Same as above less SFX
Trikafta®(elexacaftor/tezacaftor/ivacaftor)
Phe508Del + 177 others
