<p>Doxycycline is a broad-spectrum antibiotic synthetically derived from oxytetracycline <sup class="text-reference-group"><a class="reference-popover-link" data-content="Official drug label" href="#label-reference">Label</a></sup>. This drug is a second-generation tetracycline, exhibiting lesser toxicity than first-generation tetracyclines <sup class="text-reference-group"><a class="reference-popover-link" data-content="Smilack JD: The tetracyclines. Mayo Clin Proc. 1999 Jul;74(7):727-9. doi: 10.4065/74.7.727. (PubMed ID 10405705)" href="#reference-A174034">7</a></sup>. Doxycycline may be used to treat a wide range of bacterial infections, depending on the results of antibiotic susceptibility testing.</p>