Headache affects more than 40 million Americans and is one of the most common pathological conditions affecting mankind. Billions of dollars are spent each year on treatments and over-the-counter products to relieve this condition. The ingredients of one such product- Excedrin Extra Strength- will be characterized below in an attempt to understand how these over-the-counter medications work to combat headaches.

There are three primary active ingredients in Excedrin Extra Strength:

Active Ingredient Amout per Tablet Purpose
Acetaminophen >250 mg pain reliever
Aspirin 250 mg pain reliever
Caffeine 65 mg pain reliever aid

Before we get started, here is a list of useful terms for future reference:

analgesic: capable of relieving pain
antipyretic: effective in relieving fever
prostaglandins: hormone-like intracellular messengers that are involved n pain responses, fever, and redness and swelling that follow injuries. They are found in high concentrations at sites of inflammation.

Characterization of Ingredients

Acetaminophen: has both analgesic and antipyretic activity; it is not capable of reducing peripheral inflammations as can aspirin, however, so it is considered a less powerful analgesic than aspirin. This compound is a centrally acting drug and works by inhibiting cyclooxygenase (COX), an enzyme involved in prostaglandin synthesis.

Aspirin: like acetaminophen, aspirin shows analgesic and antipyretic activity; in addition, however, aspirin is also an anti-inflammatory drug. The mechanism of action for this compound is similar to that of acetaminophen (prevention of prostaglandin synthesis). Aspirin is prepared by a unique reaction called Kolbe synthesis.


 Benzoic Acid

Hydroxypropyl Methylcellulose

Microcrystalline Cellulose (aka Klucel or 2-hydroxypropyl ether)

Mineral Oil

Polysorbate 20


Propylene Glycol

Simethicone Emulsion

Sorbitan Monolaurate (aka Span 20)--  C18H34O6; light yellow liquid. Lipophilic emulsifier. Mol. mass = 346.46

Stearic Acid

Excedrin Extra Strength may also contain:

Carnauba Wax-- Melting Point ( 0C): 81-86    Specific Gravity: 0.99

FD&C Blue No.1-- C37H34N2Na2O9S3    Melting Point (0C): 283 Mol. mass = 792.84
Saccharin Sodium

Titanium Dioxide