Komiskey: Anti-tussives and Mucolytics

Question 1

You should be able to describe the pharmacology of antitussives, expectorants, decongestants, and a drug that potentiates cystic fibrosis transmembrane regulator (CFTR) gating functions used in the treatment of respiratory problems.
You should be able to list the antitussives, expectorants, and decongestants used in the treatment of respiratory problems.
You should be able to describe the toxicity of antitussives (esp. dextromethorphan) , expectorants, decongestants, and a drug that potentiates CFTR gating functions used in the treatment of respiratory problems.

Answer 1

LOs

Question 2

How/where do anti-tussives work? (narcotic and non-narcotic)

Answer 2

Cough center in the medulla

Cough centers in throat, lungs

Question 3

What is the most common OTC ingredient in non-narcotic anti-tussives? In what common medications is it found?

Answer 3

Dextromethorphan. Robitussin, Tylenol, Nyquil

Question 4

What is the ingredient in prescribed narcotic anti-tussives? What is it metabolized to in the liver?

Answer 4

Codeine; morphine

*the prescription should not last longer than one week due to addictive properties

Question 5

Do you use an anti-tussive for a productive cough or for a non-productive cough?

Answer 5

Non-productive (dry cough)

Question 6

How does benzonatate work?

Answer 6

It anesthetizes/numbs the cough reflex

Question 7

SE of benzonatate?

Answer 7

HA, dizziness, sedation

Question 8

SE of narcotic-type anti-tussive (codeine)?

Answer 8

sedation, nausea, constipation

Question 9

**SE of Dextromethorphan?

Answer 9

dizziness, drowsiness, nausea

Question 10

In which patients are opioid antitussives contraindicated?

Answer 10

premie babies or in labor when a premie is expected

COPD, asthma

Question 11

What OTC drug are teens using in mass quantities to get high?

Answer 11

Dextromethorphan

Question 12

What 3 drugs are highly dangerous and can send young people to the ER when combined with dextromethorphan?

Answer 12

non-drowsy anti-histamines
SSRI anti-depressants
MAOI inhibitors

Question 13

What is the normal dose of cough medicine?

Answer 13

15-30 mg

Question 14

What syndrome can occur in people taking dextromethorphan and how does it happen?

Answer 14

Dextrorphan binds to serotonin receptors which may contribute to its abuse potential. This also is a consideration in patients who have coingested another drug with serotonergic effects, such as the SSRIs. This combination has the potential to lead to serotonin syndrome.
There are genetic polymorphisms in CYP2D6, EMs will produce more dextrorphan and have more euphoric effects from DXM abuse than PMs
(PM: poor metabolizer; EM: extensive metabolizer)

Question 15

How does dextromethorphan work?

Answer 15

Inhibits N-methyl-D-aspartate receptor and inhibits reuptake of serotonin

Question 16

Describe the 4 plateaus of clinical effects in dextromethorphan abuse.

Answer 16

1st Plateau: 1.5-2.5mg/kg
- Mild alcohol-marijuana-like intoxication, GI
2nd Plateau: 2.5-7.5mg/kg
- Lethargy or agitation, ataxia, nystagmus, tachycardia
3rd Plateau: 7.5-15mg/kg
- Variable, often dysphoric, psychosis, disorientation, altered judgment may be severe
4th Plateau: > 15-30mg/kg
- Fully dissociative, seizures, hyperthermia, aspiration

Question 17

What works best for nasal congestion?

Answer 17

intranasal steroids

Question 18

How do decongestants work to reduce nasal congestion?

Answer 18

stimulate ALPHA RECEPTORS; act on blood vessels surrounding nasal sinuses.

sympathomimetics; stimulate the alpha-adrenergic receptors resulting in vasoconstriction=> decreased nasal hyperemia, decrease tissue edema, and decreased nasal congestion

Question 19

Do anti-histamines work to relieve nasal congestion?

Answer 19

No. Need to add a decongestant for allergic rhinitis.

Question 20

What are the 3 classifications of nasal decongestants?

Answer 20

1. Adrenergics
   - topical nasal sprays: Phenylephrine, Oxymetazoline, Naphthazoline, Tetrahydrozoline, Zylometazoline
   - oral: pseudoephedrine, phenylephrine (alpha 1), oxymetazoline (alpha 2)
2. Anticholinergics
   - Ipratropium
3. Corticosteroids

Question 21

What are the three main actions of nasal corticosteroids?

Answer 21

reduce mucosal inflammation
reduce mucosal mast cells
suppress glandular activity and vascular leakage
induction of vasoconstriction

SE: irritation and dryness

Question 22

What are the 4 mechanisms by which mucolytics decrease viscosity?

Answer 22

1. hydration
2. increase pH
3. increase ionic strength (soda bicarb)
4. rupture disulfide bond of the mucus (acetyl cysteine)

Question 23

________ ________ is a precursor of glutathione, which is a major scavenger of free radicals.

Answer 23

acetyl cysteine. (mucus fragments become less viscous and can’t bind to inflammatory debris)

Question 24

What can you use in patients with thicker more viscous mucus as seen in bronchitis, tobacco smoke, COPD, cystic fibrosis, asthma, TB, pneumonia, emphysema & ARDS?

Answer 24

acetyl cysteine

Question 25

What is the wood tar derivative seen in Robitussin and Glytuss, useful in chronic bronchial disease?

Answer 25

Gauifenessin

Question 26

What does Vicks Nyquil contain?

Answer 26

Acetaminophen
Pseudoephedrine, a decongestant,
Dextromethorphan, a cough suppressant
Antihistamine

Question 27

In CF, what gene is affected causing the Cl to be stuck?

Answer 27

Cystic Fibrosis transmembrane regulator (CFTR)

Abnormal transport of chloride and sodium across epithelium which lead to thick and viscous secretions

Question 28

What type of food should you advise your CF patient to eat when taking Ivacaftor?

Answer 28

fatty

Question 29

In comparing Ivacaftor alone to the combo drug of ivacaftor/lumacaftor, which has a better SE profile?

Answer 29

Ivacaftor alone: Improved quality of life but SE a lot: HA, oropharyngeal pain, URIs, nasal congestion, diarrhea, rash, dizziness

Combo of ivacaftor with lumacaftor: less SE. (percentage-wise)

LUMA BRINGS THE CL- CHANNEL TO THE SURFACE, AND IVA WORKS ON IT TO OPEN IT UP ONCE IT’S THERE.