Objective: The purpose of this prospective, randomized, double-blind study was to determine the effect of penicillin on pain in untreated teeth diagnosed with irreversible pulpitis.
Study design: Forty emergency patients participated, and each had a clinical diagnosis of an irreversible pulpitis. Patients randomly received a 7-day oral dose (28 capsules, 500 mg each, to be taken every 6 hours) of either penicillin or a placebo control in a double-blind manner. No endodontic treatment was performed. Each patient also received ibuprofen; acetaminophen with codeine (30 mg); and a 7-day diary to record pain, percussion pain, and number and type of pain medication taken.
Results: The administration of penicillin did not significantly (P >.05) reduce pain, percussion pain, or the number of analgesic medications taken by patients with untreated irreversible pulpitis. The majority of patients with untreated irreversible pulpitis had significant pain and required analgesics to manage this pain.
Conclusion: Penicillin should not be prescribed for untreated irreversible pulpitis because penicillin is ineffective for pain relief.