Objective: To establish the efficacy of a multidrug oral treatment with the tricyclic antidepressant agent doxepin and the cyclooxygenase (COX) inhibitor piroxicam in patients with interstitial cystitis (IC), who had failed standard therapy in an open, prospective, nonrandomized study.
Methods: A total of 37 patients diagnosed with IC received 75 mg doxepin and 40 mg piroxicam daily. The treatment was termed DOXCAM. Effectiveness of therapy was assessed with frequency-volume charts, an IC symptom score and with cystometry prior to treatment, 8 weeks after the start and 4 weeks after termination of drug treatment.
Results: Medication was not tolerated by five patients. Twenty-six of 32 patients have experienced virtual total remission of symptoms (81%) and six patients had significant relief (19%). DOXCAM treatment resulted in a significant percent decrease in pain (65% versus 21%). Daytime frequency decreased from 17.6+/-5.7 to 11.3+/-3.6 voids while nocturia did not improve significantly. Twenty-three of the 26 patients who became symptom free and four of the six patients who showed significant improvement had a return of symptoms after cessation of therapy.
Conclusion: It is reasonable to consider oral treatment with DOXCAM in those patients who have failed first-line therapies.