<p>The terminal elimination half-life of tamoxifen is 5 to 7 days, while the half-life of N-desmethyltamoxifen, the primary circulating metabolite, is approximately 14 days.<sup class="text-reference-group"><a class="reference-popover-link" data-content="FDA Approved Drug Products: Tamoxifen Oral Tablets" href="#reference-L7799">15</a>,<a class="reference-popover-link" data-content="FDA Approved Drug Products: Tamoxifen Oral Solution" href="#reference-L7802">16</a></sup></p>