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1130 SECTION X Special Topics

REFERENCES US Food and Drug Administration: Drug applications for over-the-counter drugs.
Consumer Healthcare Products Association website: http://www.chpa.org/. http://www.fda.gov/Drugs/ResourcesForYou/Consumers/ucm143551.
htm.
Handbook of Nonprescription Drugs, 18th ed. American Pharmacists Association, US National Library of Medicine: DailyMed. https://dailymed.nlm.nih.gov/
2015. dailymed/index.cfm.
Facts and Comparisons eAnswers (online). Wolters Kluwer Health, 2017.

C ASE STUD Y ANSWER

Combination OTC “cold and flu” medications typically daily over the past 72 hours. This cumulative dosage, coupled
contain analgesics (eg, acetaminophen, aspirin), antihistamines with KH’s chronic ethanol consumption (three to four glasses
(eg, chlorpheniramine, diphenhydramine), antitussives (eg, of wine daily), significantly potentiates the risk for acet-
dextromethorphan), expectorants (eg, guaifenesin), and nasal aminophen hepatotoxicity. In the USA, unintentional acet-
decongestants (eg, phenylephrine, pseudoephedrine). KH’s aminophen overdose is a leading cause of acute liver failure.
chronic prescription medications include a narcotic analgesic The warnings section on all OTC acetaminophen-containing
combination product that provides 2600 mg of acetamino- products clearly state that severe liver damage may occur when
phen and 40 mg of hydrocodone. Over the past few days, consumers: (1) take dosages >4000 mg in 24 hours; (2) use
KH has added two different OTC acetaminophen-containing acetaminophen in combination with other drugs containing
products including Alka-Seltzer Plus Severe Cold + Flu acetaminophen; or (3) take acetaminophen and drink three or
(650 mg acetaminophen/2 tablets) every 4 hours and Tylenol more alcoholic beverages daily. Unfortunately, many consum-
PM (1000 mg acetaminophen/2 tablets) at bedtime. The clini- ers do not carefully read OTC medication labels, and many
cian should obtain a detailed medication history to determine do not appreciate the amount of acetaminophen “hidden” in
the actual total dose of acetaminophen consumed, but it is combination prescription and OTC products.
likely that KH has ingested more than 6 g of acetaminophen