Resp drugs

Question 1

Name the types of bronchodilators?

Answer 1

beta agonists
Short acting: Salbutamol (ventolin) and terbutaline (bricanyl)
Long acting: Salmeterol (Serevent) and formoterol

Muscarinic antagonists:
Short acting: Ipratropium
Long-acting: Tiotropium

Question 2

Beta agonists MOA? examples? SEs? Interactions?

Answer 2

act on beta 2 receptors to relax SM and reduce mucus secretion

Short-Acting, Fast Onset
- 2-4hrs
- Salbutamol: Ventolin
- Terbutaline: Bricanyl
Long-Acting
- 12-18hrs
- Salmeterol: Serevent
- Formoterol (Fast onset)

SEs: Tremor, tachycardia

Interactions: Lower K+ if given with Corticosteroids

• Loop / thiazide diuretics
• Theophylline

Salbutamol can be given IVI in acute severe asthma.

Question 3

Muscarinic antagonists examples? MOA? SEs? CIs?

Answer 3

Short-Acting
- 3-6hrs
- Ipratropium: Atrovent
Long-Acting
- Tiotropium: Spiriva

Bronchodilatation
↓ mucus secretion

SEs: Dry mouth

Caution: Closed angle glaucoma, prostatic hypertrophy

Question 4

Types of inhaled corticosteroid?

Answer 4

Beclomethasone
Budesonide
Fluticasone

Symbicort: Budesonide + formoterol
Seretide: Fluticasone + salmeterol

Question 5

Inhaled corticosteroid MOA? SEs? How to reduce risk of complications?

Answer 5

Act over wks → ↓ inflammation
- ↓ cytokine production
- ↓ prostaglandin / leukotriene
synthesis
- ↓IgE secretion
- ↓ leukocyte recruitment
Prevent long-term ↓ in lung function

SEs: Oral candidiasis. High doses –> typical steroid SEs

To reduce risk of complications: Use a spacer, rinse mouth after use.

Question 6

Theophylline MR and aminophylline MOA? SEs? Interactions? Administration?

Answer 6

Methylxanthines
PDE inhibitors
- ↑cAMP → bronchodilatation

SEs: Nausea, Arrhythmias, Seizures, ↓ K

Reduced levels: Smoking, alcohol, CyP inducers
Raised levels: CCBs, CyP inhibitors

Aminophylline is IV form
- give IVI slowly
- Too fast → VT
- monitor c¯ ECG and
check plasma levels

Question 7

Montelukast, Zafirlukast MOA? SEs? Use?

Answer 7

Leukotriene receptor antagonist
- Block cysteinyl leukotrienes

? Churg-Strauss

Use: Particularly useful for NSAID and
exercise-induced asthma

Question 8

Name two mucolyytic drugs? SEs? CIs? Uses?

Answer 8

Carbocysteine:
SE: GI bleed (rare)
CIs: Active peptic ulceration
use: COPD

Dornase ALFA (DNase):
Use: CF

Question 9

Name antihistamines. MOA? SEs? CIs?

Answer 9

Non-sedating
- Certirizine
- Des-/ Loratidine: Clarityn
- Fexofenadine
Sedating
- Chlorphenamine: Piriton

Selective H1 R inverse agonists - aka H1 antagonists

SEs:
Hypotension
Arrhythmia: ↑ QT
Older agents
- Drowsiness
- Anti-AChM

CI: Severe hepatic disease

Caution: Long QT; BPH; closed angle glaucoma

Question 10

General measures of Chronic Asthma Tx?

Answer 10

TAME

Technique for inhaler use
Avoidance: allergens, smoke (ing), dust
Monitor: Peak flow diary (2x/d) - Written instruction based on peak flow
Educate:
 Liaise c¯ specialist nurse
 Need for Rx compliance
 Emergency action plan

Question 11

Outline the drug ladder for Chronic asthma?

Answer 11

1 SABA PRN
 If use >1/d or nocte symptoms → step 2

2 Low-dose inhaled steroid: beclometasone 100-400ug bd
 200ug bd is good starting dose for most

3 LABA: salmeterol 50ug bd
 Good response: continue
 Benefit but control still poor: ↑ steroid to 400ug bd
 No benefit: discontinue + ↑ steroid to 400ug bd

If control is still poor consider trial of:
 Leukotriene receptor antagonist (e.g. monetelukast) - Esp. if exercise- or NSAID-induced asthma
 MR Theophylline

4 Trials of
 ↑ inhaled steroid to up to 1000ug bd
 Leukotriene receptor antagonist
 MR Theophylline
 MR β agonist PO

5 Oral steroids: e.g. prednisolone 5-10mg od
 Use lowest dose necessary for symptom control
 Maintain high-dose inhaled steroid
 Refer to asthma clinic

Question 12

COPD Severity ranges?

Answer 12

Mild: FEV1 >80% (but FEV/FVC <0.7 and symptomatic)
 Mod: FEV1 50-79%
 Severe: FEV1 30-49%
 Very Severe: FEV1 < 30%

Question 13

COPD General measures of Mx?

Answer 13

Stop smoking
 Specialist nurse
 Nicotine replacement therapy
 Bupropion, varenicline (partial nicotinic agonist)
 Support programme

Pulmonary rehabilitation / exercise

Rx poor nutrition and obesity

Screen and Mx comorbidities e.g. cardiovasc, lung Ca, osteoporosis; Depression

 Influenza and pneumococcal vaccine
 Review 1-2x/yr
 Air travel risky if FEV1<50%

Question 14

COPD Tx if chronic productive cough? Breathlessness and/or exercise limitation? Exacerbations or persistant breathlessness?

Answer 14

CHronic productive cough: Mucolytics (Carbocysteine)

Breathlessness and/or exercise limitation
 SABA and/or SAMA (ipratropium) PRN
 SABA PRN may continue at all stages

Exacerbations or persistent breathlessness
 FEV1 ≥50%: LABA or LAMA (tiotropium) (stop SAMA)
 FEV1 <50%: LABA+ICS combo or LAMA

Persistent exacerbations or breathlessness:
 LABA+LAMA+ICS
 Roflumilast / theophylline (PDIs) may be considered
 Consider home nebs

Question 15

Indications for LTOT with COPD?

Answer 15

Assess patient if any of the following:
very severe airflow obstruction (FEV1 < 30% predicted) (Assessment should be ‘considered’ for patients with severe airflow obstruction (FEV1 30-49% predicted)
cyanosis
polycythaemia
peripheral oedema
raised jugular venous pressure
oxygen saturations less than or equal to 92% on room air

Offer LTOT to patients with a pO2 of < 7.3 kPa or to those with a pO2 of 7.3 - 8 kPa and one of the following: secondary polycythaemia
peripheral oedema
pulmonary hypertension

Question 16

Aims of LTOT?

Answer 16

should maintain PaO2 from >8.0kPa for 15hr per day.

Question 17

Types of pulmonary rehab for COPD patients?

Answer 17

Consider LTOT if PaO2 <7.3kPa (see ‘Long-term O2 therapy’, earlier in topic OPPOSITE).
Surgery may be appropriate in selected patients, eg recurrent pneumothoraces;
isolated bullous disease. Lung volume reduction/endobronchial valve/transplant.
• NIV may be appropriate if hypercapnic on LTOT.
• NB: air travel is risky if FEV1 <50% or PaO2 <6.7kPa on air.
• Consider palliative care input.