Antitussives Flashcards
steps for treating cough?
Step 1 - identify the cause
Step 2 - choose appropriate therapy
Step 3 - follow-up
what are drug classes that can treat cough?
o Antihistamines o Glucocorticoids o Antitussives (cough suppressants) o Expectorants o Leukotriene Receptor Antagonists o Beta-2 Adrenergic Agonists o Anticholinergic
what are the 2 Major Categories of Antitussives?
o Centrally-acting
o Peripherally-acting
where do Peripherally-acting antitussives work?
in the lungs
how do Centrally-acting antitussives work?
decreases the sensitivity of cough receptors and interrupts cough impulse transmission by depressing the medullary cough center
(Work in CNS, brain. Inhibit impulse that comes into brain that tells your body to cough. Part of the medulla oblongata controls cough. )
Most common antitussive that we use?
Dextromethorphan
what drug is a Centrally-acting, non-opioid antitussive agent
Dextromethorphan
is Dextromethorphan structurally related to codeine?
yes, it is Structurally related to codeine
Dextromethorphan is Labelled for OTC use in pt >_ years of age
less than 4 years of age
what is a contraindication for Dextromethorphan?
concurrent MAOI (monoamine oxidase inhibitor) use +/- 2 weeks
what are warnings of Dextromethorphan?
o Serotonin syndrome
To much serotonin in the brain can cause this and can be fatal
o Abuse/misuse
It is abused and misused often by teenagers
Some people get euphoric from it because it is structurally related to codeine. Some people get really sleepy from it, and some get euphoric and it alters mood.
what are ADRs of Dextromethorphan?
CNS: confusion, excitement (why it might be abused), irritability, nervousness, drowsiness/sedation
DDI of Dextromethorphan?
substrate of several CYP isozymes (2D6, 3A4, 2C9, etc.)
Opioid Derivative agents for antitussives?
o Hydrocodone (CII) o Codeine - off-label
what is a warning when prescribing Opioid Derivative antitussive medications?
High risk for dependence and abuse/misuse
what is a warning when prescribing Opioid Derivative antitussive medications?
High risk for dependence and abuse/misuse
when should you use caution when prescribing Opioid Derivative antitussive medications?
o Any other CNS drug o CNS diseases o Respiratory disease o Renal/liver impairment o Debilitated patients o Elderly o Bowel, thyroid, prostate, eye diseases
what are ADRs of Opioid Derivative antitussive medications?
o CNS: sedation, confusion, dysphoria, euphoria, fear, mood swings, mental impairment o Derm: pruritus, rash o GI: constipation, n/v o Resp: respiratory depression o GU: urinary retention, bladder spasms
Suggested Uses for Opioid Derivative antitussive medications?
o Cough is severe (e.g. significant impact on QOL)
Impacting ability to sleep
o Mainly/only for bedtime dosing
o If DM or other drug fails and cough is severe
is benzonatate OTC?
NO
PO soft gel form of benzonatate is referred to as a ___.
perle
how does benzonatate work? (MOA)
Presumably acts by anesthetizing stretch receptors in the lungs and pleura
what are the ADRs for benzonatate?
o ADRs are almost non existent
o Rare isolated CNS disturbances causing abnormal behavior
o Rare but severe hypersensitivity reactions have been reported
Antitussives can be used for symptomatic control of ______ cough
acute (<3 week)
If cough present ≥3 weeks, what is next step?
thorough workup needed
If etiology of cough cannot be identified, no specific therapy exists, or specific therapy has failed, what agent should you start with?
dextromethorphan
what antitussive can be used if the cough persists and/or there is concern for drowsiness
benzonatate
