PHARM: Cough Suppressants, Decongestants, Mucolytics Flashcards
How many phases are there of a cough?
3: Inspiratory phase, compressive phase, expulsive phase
Describe the 3 phases of a cough.
1) Inspiratory effort
2) Forced expiratory effort against a closed glottis
3) Opening of the glottis and rapid expiratory airflow
Where are cough receptors located?
airway bifurcations in the larynx and distal esophagus
Though what nerves to cough afferents link to the cough center/cerebral cortex?
vagus and superior laryngeal nerves
True or false: afferent pathways control the muscle response that leads to cough.
FALSE: efferent pathways do
What type of cough lasts less than three weeks?
acute
What type of cough lasts three to eight weeks?
subacute
What type of cough lasts greater than 8 weeks?
chronic
Malodorous secretions with cough indicate what type of infection?
anaerobic
What is an antitussive?
drug to prevent (nonproductive) cough
Antitussives are divided into what two groups?
Systemic
Topical
List some systemic antitussives.
Dextromethorphan
Diphenhydramine
Codeine
List some topical antitussives.
Camphor
Menthol
What is an expectorant?
drug to help productive coughs (with thick secretions) bring up mucus
What is an example of an expectorant?
Guaifenesin
What is the MOA of dextromethorphan?
Supresses the cough reflex by a direct action on the cough center int he medulla of the brain
How is dextromethorphan metabolized?
CYP2D6 into its active metabolite (dextrorphan)
What are the side effects of dextromethorphan?
Dizziness, drowsiness, N/V, diarrhea, excitability, trouble sleeping; HALLUCINOGENIC (pseudobulbar effect)
Dextromethorphan is contraindicated in what individuals?
those on MAOI antidepressants**
those who have advanced respiratory insufficiency, hepatic disease, or hypersensitivity
What is diphenhydramine?
Benadryl
What type of drug is diphenhydramine?
Antihistamine-H1 receptor antagonist
What is the MOA of diphenhydramine?
Supresses cough reflex by direct effect on cough center and due to its anticholinergic effects
What are some side effects of diphenhydramine?
Drowsiness Respiratory depression blurred vision Urinary retention constipation
In what patients is diphenhydramine contraindicated?
Prostate hypertrophy urinary obstruction asthma COPD peptic ulcers MAOI takers
What type of drug is codeine?
opioid analgesic and antitussive (related to morphine but has lower affinity for mu receptors)
How does codeine depress the cough reflex?
direct action on cough center in CNS
What are some side effects of codeine?
constipation sedation histamine release vasodilation orthostatic hypotension dizziness
In what people is codeine contraindicated?
hypersensitivity Pregnant women Prostatic hypertrophy patients Individuals on sedatives People with asthma, OCPD, or ARD
Topical agents can come in what forms?
Ointments (to rub on throat)
Lozenges
Inhalation (breathe in medicated vapors)