Drugs for Cough and Cold Flashcards
What are the drugs for a beneficial cough?
None, do not medicate
What are the drugs for a non-beneficial dry cough?
Antitussives:
1) Codeine
2) Dextromethorphan
3) Diphenhydramine
What are the drugs for a productive non-beneficial cough?
1) Expectorants:
- Guanifesin
2) Mucolytics:
- Acetylcysteine
- Carbocisteine
3) Mucokinetic
- Bromhexine/ambroxol
What are the drugs for rhinorrhoea/nasal congestion/post-nasal drip?
1) Mucoregulator
- Ipratropium
2) Mast cell stabiliser
- cromoglicic acid
3) Antihistamine
4) Decongestants
- sympathomimetics
- nasal glutocorticoids
What is the moa of ipratropium?
Mucoregulator:
- SAMA → blocks M3 activation of submucosal/goblet cells mucus secretion
- ↓mucus and sputum
(does not dry basal secretion/↑ viscosity)
What are 2 AEs of ipratropium?
Few as little enters systemic circulation via intranasal route:
- unpleasant taste
- dry mouth
- urinary retention in elderly
Why is compliance in px Rx Ipratropium and Cromoglicic acid a concern?
Both have unpleasant/bitter taste
What is the moa of Cromoglicic acid?
Mast cell stabiliser:
Controls Cl- channels → inhibit cellular activation
1) ↓mast cell granulation by IgE FcεRI crosslinking
2) ↓secretion of inflammatory mediators from eosinophils, neutrophils, macrophages
3) ↑secretion of annexin A1 → inhibit prostaglandin and leukotriene production
What are 2 AEs of cromoglicic acid?
1) Unpleasant/bitter taste
2) Throat/nasal irritation
3) Mouth dryness
4) Cough
What are 2 nasal glucocorticoids used as nasal decongestants?
1) Fluticasone (rose water odor)
2) Mometasone
What is the moa of nasal glucocorticoids (eg. fluticasone, mometasone)?
Anti-inflammatory (COX inhibition → ↓PGI2 and PGE2) → ↓congestion and mucus secretions
What is the main AE of nasal glucocorticoids (eg. fluticasone, mometasone)?
Local mucosal dryness and irritation
(Systemic side effects limited by intranasal delivery)
How is ipratropium administered?
Intranasal/oral inhalation
How is Cromoglicic acid administered?
Intranasal/inhaled
How are nasal glucocorticoids (eg. fluticasone, mometasone) administered?
Intranasal
How are sympathomimetics used ass decongestants administered?
Oral or intranasal
What are 3 examples of sympathomimetic agents used as nasal decongestants?
1) Direct α adrenoceptor agonists
a) α-1 selective: Phenylephrine (oral or intranasal)
b) Non-selective: Oxymetazoline (intranasal) / naphazoline (intranasal)
2) Indirect ↑ NE/E release
a) Pseudoephedrine (oral) / Ephedrine (intransal)
What is the moa of sympathomimetics used as nasal decongestants?
α-agonism / Indirect → ↑NE/E
→ Vasoconstriction of nasal blood vessels → ↓ inflammation and mucus secretion
What are 3 AEs of sympathomimetic agents used as nasal decongestants (eg. phenylephrine, pseudoephedrine)?
1) Rebound congestion
- prolonged (>days) use of topical intranasal decongestants
2) CNS stimulation
- more likely with oral decongestants
- restlessness, tremors, irritability, anxiety, insomnia
3) CVS
- more likely with oral decongestants
- HTN (2° to vasoconstriction)
- Tachycardia (indirect sympathomimetics eg. pseudoephedrine)
When are nasal glucocorticoids (eg. fluticasone, mometasone) contraindicated?
<4 y/o
When are sympathomimetic agents used as nasal decongestants (eg. phenylephrine, pseudoephedrine) contraindicated?
Caution in elderly and <12 y/o
What are 3 antitussives?
In order of potency, decreasing order of addictiveness
Opioid:
1) Codeine
Non-opioid:
2) Dextromethorphan
3) Diphenhydramine
What are 2 AEs of using codeine as an antitussive?
1) CNS sedation
2) Abuse @ high dose (weak opioid)
3) Respiratory depress (only at @ dose)
- risk in px with severe respiratory insufficiency
4) Do not combine with other CNS depressants
5) Do not combine with CYP2D6 ultra-rapid metabolisers
What are 2 AEs of using dextromethorphan as an antitussive?
1) CNS:
- drowsiness, dizziness, confusion, insomnia, excitement, nervousness
2) GIT
- nausea, vomiting, stomach pain
3) Abuse at high dose
- dissociative anaesthetic-like effect
4) Others:
- nonselective serotonin reuptake inhibitor
- sigma-1 receptor agonist
- (at high-dose) NMDA receptor block
What are 2 AEs of using Diphenhydramine as an antitussive?
1) Sedative
2) Anticholinergic
How antitussives (eg. codeine, diphenhydramine, dextromethorphan) administered?
Oral
How are expectorants (eg. guaifenesin) administered?
Oral
When is codeine contraindicated?
1) <18
2) With other CNS depressants
3) With other CYP2D6 ultra-rapid metabolisers
When is dextromethorphan not recommended?
<4 years old
What is the moa of guaifenesin?
↑ production of respiratory tract fluids → liquefy + ↓ viscosity of tenacious secretions
What are 2 AEs of guaifenesin?
1) GI disturbances
2) Nausea
What should px taking guaifenesin be advised?
Take adequate fluid to make secretions less viscous and protect renal function (nephrolithiasis reported on overdose)
When is guaifenesin contraindicated?
1) <2 y/o (caution <6)
2) persistent cough associated with asthma or smoking
When are mucolytics (eg. acetylcysteine, carbocisteine) contraindicated?
1) Elderly or debilitated px with severe respiratory insufficiency
2) px with asthma
3) Carbocisteine for px with active PUD
How are mucolytics (eg. acetylcysteine, carbocisteine) administered?
1) Inhalation
2) Effervescent tablets
3) Oral granule/syrups
What is the moa of mucolytics (eg. acetylcysteine, carbocisteine)?
Free sulfhydryl group opens disulphide bonds in mucoproteins → ↓ mucous viscosity
What are 2 AEs of mucolytics (eg. acetylcysteine, carbocisteine)?
1) Bronchospasm
2) Anaphylactoid rxns (rash, hypotension, dyspnea, wheezing)
3) GI disturbances
What are 2 examples of mucolytics?
1) Acetylcysteine
2) Carbocisteine
What is an example of an expectorant?
Guaifenesin
What is an example of a mucokinetic?
Bromhexine
and its active metabolite ambroxol
What is the moa of mucokinetics (eg. bromhexine, ambroxol)
Mucokinetic: promotes mucus clearance
1) ↑ ciliary beat frequency
2) ↑ adherence of mucus to cilia
3) Stimulate surfactant production (prevent mucus sticking to walls)
4) Antioxidant as free radical scavenger
5) Anti-inflammatory by ↓ cytokines
6) Suppresses influenza virus multiplication
7) Local anesthetic by blocking voltage-gated Na+ channel
What are 2 AEs of mucokinetics (eg. bromhexine, ambroxol)?
1) Allergic rxn
2) Cutaneous AEs
When should mucokinetics (eg. bromhexine, ambroxol) be avoided?
1) px with Hx of asthma and PUD
2) caution <6 y/o
3) contraindicated <2y/o
What is the best medication for cough and cold in pediatric px?
None, just observe, mostly self-limiting.
Which of the cough and cold medications are safe for pediatric use?
None <2y/o
Which of the cough and cold medications are safe for geriatric use?
1) expectorants (Guaifenesin)
2) Mast cell stabilisers (Cromoglicic acid)
3) Mucoregulators (Ipratropium)
4) Nasal glucocorticoids (fluticasone, mometasone)
