Cough+Cold/Pharyngitis/Sinusitis/Acute Otitis Media/Mastoiditis Pharmacology

Common Cold

PP: viral infection of upper respiratory tract

RF: smoking
very young
very old
recent exposure to infected contacts

E: rhinovirus
preschool-aged (average: 3-8 times/year)
elementary school-aged (average: 3-8 times/year)

CM: rhinorrhea
nasal obstruction
sneezing
cough
contagious period→until sx persist

TX: no antibiotics
self limiting
sx relief

Cough+Etiology

PP: mechanical/chemical stimuli→forceful expulsion of air→removes irritant in airway
mechanism poorly understood

E: asthma
smoking infection
lung cancer
GERD/GI sx
allergic rhinitis
bacterial sinusitis
lisinopril/ACE inhibitors
cough hypersensitivity syndrome

Cough Tx Considerations

identify+treat cause:

• palliative tx used until source problem resolved

postnasal drip: PO antihistamines
nasal decongestants
intranasal steroids

ACE inhibitor: change to ARBs

acid reflux associated cough: H2 receptor antagonist (rantidine)
PPI (omeprazole)

URI→don’t suppress cough→clears mucus from lungs+improves breathing

acute vs chronic cough

dry vs productive (mucus) cough

Tx Goals

use NP as 1st line: rest
increased fluid intake

reduce severity of sx

observe course of infection

Nonpharmacologic/NP Tx

disinfect environment

wash hands regularly

rest

hydration

position mattress at 45° angle

maintain comfortable temperature+humidity

stop smoking+alcohol

Cough/Cold Pharmacologic/Mx Tx

topical/PO/nasal decongestants ±antihistamines

intranasal anticholinergic

non-steroidal anti-inflammatories (NSAIDS)

antitussives

mucolytics

Pseudoephedrine

MX: decongestants

MOA: direct alpha+beta agonist→vasoconstriction+bronchiole relaxation (respectively)

I: reduce pain
fever

ROA: IR
ER tablets
behind the counter+prescription restrictions
acute cough→add antihistamine

AE: increased BP
increased HR
CNS sx: restlessness
insomnia
anxiety
stimulation
headaches

CI: uncontrolled HTN
narrow angle glaucoma

Phenylephrine+Nasal Oxymetolazine

MX: decongestants

MOA: direct alpha antagonist→vasoconstriction

I: reduce pain
fever

ROA:
PE: nasal spray
PO tablets

O: nasal

over the counter
acute cough→add antihistamine

AE: PE less effective than pseudoephedrine

topical/nasal: little systemic absorption
palpitations
headaches

prolonged use (over 3+ days)→rebound congestion

1st Generation Antihistamines

MX: diphenhydramine
chloropheniramine

MOA: non-selective competitive antagonist of histamine H1 receptor

I: reduce pain
fever

ROA: Q 4-6 hours

AE: more anticholinergic sx than 2nd gen AH
CNS effects→increased fall risk
kids→paradoxical stimulation

CI: elderly
bladder obstruction
benign prostatic hyperplasia (BPH)
narrow-angle glaucoma

2nd Gen Antihistamines

MX: cetirizine
loratidine
levocetirizine
desloratadine
fexofenadine

MOA: selective competitive antagonist of histamine H1 receptor

I: reduce pain
fever

AE: fewer anticholinergic effects
don’t act centrally: larger protein→difficulty crossing BBB
don’t work as quickly as 1st gen→last longer

Intranasal Anticholinergic

MX: ipratropium 0.06%
Rx nasal spray

I: reduce pain
fever

MOA: inhibits serous+seromucous gland secretions→dries up runny nose→improves rhinorrhea (doesn’t improve nasal congestion)

AE: nasal dryness
epistaxis (nose bleeding)
headache

CI: don’t use more than 4+ days
narrow angle glaucoma
benign prostatic hypertrophy (BPH)
pregnancy
lactation

Ibuprofen

MX: NSAID

MOA: inhibits COX-2 enzyme→reduces inflammation

I: reduce pain
fever

ROA: PO
onset→30-60 min
half life→4 hours→take q4-6h

AE: abdominal cramps
nausea
indigestion

CI: peptic ulcers
GI hemorrhage
prolonged bleeding time
mild liver enzyme elevations
acute kidney injury (AKI)

CI MX: P2Y12 inihibitors
other NSAIDS
SSRIs
anticoagulants
alcohol
aminoglycosides
ARBs
ACEs

Black Box:
cardiovascular effects: increased BP→increased stroke risk
GI effects
renal impairment
pregnancy
lactation
babies under 6 months

Prostaglandins vs NSAIDs Effects On Kidney

prostaglandins:

• increased arteriole vasodilation

• increased blood flow

NSAIDS:

• decreased prostaglandin concentration

• decreased bloodflow to kidney→can cause damage

NSAIDS Effects On Gut

take with food:

• protects GI lining

• gets rid of stomach defenses→ulcers→mucosal injury+bleeding+more ulcers

Acetaminophen

MOA: activates descending serotonergic inhibitory pathways in CNS→decreases pain

inhibitors hypothalamic heat-regulating centers

overdose: depletes glutathione
overdose tx: activated charcoal
n-acetylcysteine

ROA: PO
PR
IV
q 4-6 hrs
onset→30-60 min
half life→4 hrs
do not exceed 4+ grams/day→unintentional overdose

CI: acute hepatic failure
hepatotoxicity
heavy alcohol use
alcoholic liver disease

CI MX: several CYP enzymes (interactions infrequent/rare)
warfarin
phenytoin

Black Box: max dose→liver toxicity
prophx→pt education

Expectorants

MX: guaifenesin

MOA: increases hydration of respiratory tract→decreases mucus viscosity→improved mucous clearance

I: productive cough

ROA: IR
ER
liquid solution
syrup
over the counter
can combine with codeine
recommended increase in water intake→increases mucous viscosity

AE: nausea
vomiting
upper respiratory infection (URI)→decreases cough reflex

sxs not improving in 7 days→reach out to provider

Antitussives

MX: dextromethorphan
codeine

MOA: decreases sensitivity of cough receptors+depresses medullary cough center

I: dry cough

AE: nausea
vomiting
constipation
upset stomach

CI:

DM: structurally related to morphine
low doses→does not contain addictive/analgesic qualities
high doses→addictive quality

C: combination with 1+ non-codeine ingredient
analgesic properties→addictive
impaired respiratory reserve
substance abuse hx
other respiratory depressants

NMDA Receptor Antagonist

MX: benzonatate

MOA: anesthetic action→suppresses respiratory stretch receptor action

I: dry cough

AE: dizziness
dysphagia
seizures
generally ineffective

Honey

MOA: teens (1-18 y/o)→can be used as an antitussive+improves sleep

AE: nervousness
insomnia
hyperactivity

CI: worse than dextromethorphan

Combination Txs

dayquil: phenylephrine (decongestant)+dextromethorphan (cough suppressant)+acetainophen (pain reliever)

nyquil: phenylephrine (decongestant)+dextromethorphan (cough suppressant)+acetaminophen (pain reliever)+doxylamine (antihistamine)

mucinex DM: guaifenesin (expectorant)+dextromethorphan (cough suppressant)

claritin D: laratadine (antihistamine)+pseudoephedrine (decongestant)

caution of acetaminophen content in combination products