Page 1134 - Basic _ Clinical Pharmacology ( PDFDrive )

63 Therapeutic &
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Toxic Potential of

Over-the-Counter Agents

Valerie B. Clinard, PharmD, &
Robin L. Corelli, PharmD

C ASE STUD Y

KH, a 55-year-old woman, presents to the emergency Her social history is significant for alcohol use (three to four
department with nausea, vomiting, and complaints of new- glasses of wine/night). Her vital signs include the following:
onset flu symptoms over the past several days. Her past medical temperature 99.8°F, blood pressure 132/64 mm Hg, pulse
history is significant for allergic rhinitis and chronic lower 78 bpm, and respiratory rate 15/min. On physical examination,
back pain secondary to a work-related fall 2 years ago. Her she had left upper abdominal tenderness with evidence of
current medications include Norco 5/325 (hydrocodone 5 mg/ hepatomegaly and mild scleral icterus. Laboratory data revealed
acetaminophen 325 mg per tablet; two tablets four times daily the following: alanine aminotransferase, 527 IU/L (normal
for pain) and loratadine (10 mg daily). The patient also reported 10–35 IU/L); aspartate aminotransferase, 425 IU/L (normal
recent use of several over-the-counter (OTC) medications over < 35 IU/L); and bilirubin, 2.9 mg/dL (normal 0.1–0.3 mg/dL).
the past 3 days to treat the new-onset flu symptoms, including What medications do OTC cold and flu preparations typically
Alka-Seltzer Plus Severe Cold + Flu (two tablets every 4 hours contain? Which of the OTC medications might have contrib-
during the day) and Tylenol PM (two tablets at bedtime). uted to the patient’s current symptoms?

In the USA, medications are divided by law into two classes: different systemic analgesic products, almost all of which contain
those restricted to sale by prescription only and those for which aspirin, acetaminophen, nonsteroidal anti-inflammatory drugs
directions for safe use by the public can be written. The latter (NSAIDs) such as ibuprofen, or a combination of these agents as
category constitutes the nonprescription, or over-the-counter primary ingredients. They are made different from one another
(OTC), medications. This category does not include supplements by the addition of questionable ingredients such as caffeine or
(vitamins, minerals, herbals, and botanicals), which are subject antihistamines; by brand names chosen to suggest a specific use
to different regulatory requirements (see Chapter 64, Dietary or strength (eg, “women’s,” “migraine,” “arthritis,” “maximum”);
Supplements & Herbal Medications). In 2016, the American or by special dosage formulations (eg, enteric-coated tablets, gel
public spent approximately $34 billion on OTC products to self- tabs, liquids, orally disintegrating strips and tablets, sustained-
manage a wide variety of acute and chronic medical conditions. release products, powders, seltzers). Generally, a price is attached
It is apparent that many OTC medications are comparable to all of these features, and in most cases, a less expensive generic
products advertised to consumers in ways that suggest signifi- product can be equally effective. It is probably safe to assume that
cant differences between them. For example, there are over 100 the public is generally overwhelmed and confused by the wide

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