33831 Doxycycline hyclate vs monohydrate: What is being prescribed and what are patients receiving

Abstract

Background: Doxycycline is most commonly available as a hyclate or monohydrate, differing in their salt form. Less soluble doxycycline monohydrate has been found to have less gastrointestinal side effects, but literature demonstrating differences in patient experience among the two forms is lacking. Insurance coverage, physician preference as well as pharmacy availability may determine which form the patient ultimately receives. In this quality control study, we sought to determine which form of doxycycline providers are more likely to prescribe, as well as which form pharmacies are more likely to give to patients. Methods: For this IRB exempt study, the charts of 131 patients prescribed doxycycline at their last dermatology office visit at Tulane Medical Center were surveyed regarding form received, explanation by provider of potential side effects and what side effects were experienced. Results: Of 131 patients, 87 were prescribed doxycycline hyclate, while 41 were prescribed doxycycline monohydrate. While only 30 patients were able to be reached to determine which form they picked up from the pharmacy, 27 of those patients received the form that their provider had prescribed (90%: 17 hyclate and 10 monohydrate), 2 received an alternate form (prescribed monohydrate and given hyclate) and one never picked up their prescription. Conclusion: This ongoing research demonstrates that in most cases, the form of doxycycline received matched the form prescribed, regardless of monohydrate or hyclate. This research can expand to include differences in effectiveness, tolerability, and cost between doxycycline monohydrate and doxycycline hyclate which can help guide providers use of doxycycline.