Authors: Troullos ES, Freeman RD, Dionne RA.
Title: The scientific basis for analgesic use in dentistry.
Journal: Anesth Prog
Date: May 1986
Citation: 33(3):123-38
Category: Endodontic Pharmacology
Evidence-based Ranking: 5
Purpose/Objectives: To review the therapeutic and toxic effects of analgesic drugs commonly used in dentistry.

Discussion: Salicylates, in the form of willow bark, were introduced into medicine as analgesics in 1763. Aspirin and other nonsteroidal anti-inflammatory drugs selectively inhibit prostaglandin synthesis by blocking the initial oxygenation of arachidonic acid by cyclo-oxygnease. Aspirin is a week acid that is well absorbed from the gastrointestinal tract when taken orally. It is widely distributed in the body and is excreted in the urine mostly as salicyluric acid. It is metabolized mainly in the liver by conjugation. Aspirin has several side effects which are frequently the reasons for using other NSAID’s in its place. The most frequently reported side effects are ulceration, epigastric distress, nausea, and vomiting. Aspirin should not be given to patients with liver disease, hypoprothrombinemia, hemophilia or vitamin K deficiency. It should also be avoided in patients who are taking anticoagulant drugs. Diflunisal is a derivative of salicylic acid whose major advantage over aspirin is it 8 – 12 hour duration. For mild to moderate pain, an initial dose of 1000 mg followed by 500 mg every 12 hours is recommended by the manufacturer for most patients. Propionic acid derivatives- most commonly used in dental practice are ibuprofen and naproxen. Due to their ability to cause salt and water retention they should be used with caution in individuals with a history of hypertension or heart failure. Acetaminophen was introduced in 1893. It is generally accepted to be equally effective to aspirin with fewer side effects; however, it lacks significant anti-inflammatory activity. It has a half-life of about 3 to 4 hours, is biotransformed mainly in the liver and excreted by the kidney. The maximum recommended daily dose is four grams. The mechanism of action of acetaminophen is still unclear. It is a weak inhibitor of prostaglandin synthesis, but is appears to be more active in the CNS than in the periphery. No advantage has been documented for combinations containing other putative analgesic adjuvants, such as caffeine or barbiturates. Severe pain of dental origin would probably be best treated by a combination of a NSAID plus a narcotic.

Reviewer’s Comments: Good review of analgesic drugs