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Published on: September 12, 2018
Doxycycline serum levels at the time of dilation and evacuation with two dosing regimens
Matthew F Reeves1, Patricia A Lohr, Jennifer L Hayes
1Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, and Magee-Women's Research Institute, Pittsburgh, PA 15213, USA. mreeves@upmc.edu
Background:
Doxycycline is commonly used for antibiotic prophylaxis before dilation and evacuation (D&E) but frequently causes nausea and emesis which may affect absorption and effectiveness. Taking doxycycline the night prior to surgery may result in adequate absorption with better tolerance.
Study Design:
We enrolled 40 women into a double-blind randomized comparison of doxycycline 200 mg given 4 h before D&E (Group 1) vs. the night prior to D&E with dinner (Group 2). D&E procedures were scheduled after 11 a.m. and subjects were nil per os on the morning of the procedure. Subjects completed symptom diaries from dilator placement until the D&E. Serum for doxycycline assays was obtained before the D&E.
Results:
Mean gestational age was 19.4 weeks (range 15.8-22.0 weeks) and did not differ by group. Serum was collected at 3.2 h (range 1.9-4.8 h) and 16.3 h (range 13.8-19.1 h) after ingestion of doxycycline in Groups 1 and 2, respectively. Median serum doxycycline levels (milligrams per liter) were 2.7 and 1.8 for Groups 1 and 2, respectively (p=.04). Emesis was experienced by 50% and 15% of women in Groups 1 and 2, respectively (p=.04). Nausea ratings were worse after doxycycline in the morning compared to doxycycline with dinner and compared to placebo at either time (all p<.01). Emesis following doxycycline consumption was not associated with lower doxycycline levels (p>.2).
Conclusion:
When given with food on the night prior to D&E, doxycycline results in less emesis and nausea, but results in lower serum levels at the time of D&E.
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