<p><strong>Pharmacodynamics</strong>: Miconazole possesses an antifungal activity against the common dermatophytes and yeasts as well as an antibacterial activity against certain gram-positive bacilli and cocci. Its activity is based on the inhibition of a demethylation step in the ergosterol biosynthesis. Ergosterol, the end-product of the biosynthetic pathway and the main sterol in yeast and fungi. The disruption in production of ergosterol disrupts the fungal cell membrane, causing holes to appear in it. These holes allow the essential constituents of the fungal cells to leak out and ultimately the fungal cells die.<br />
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<strong>Pharmacokinetics</strong>: The oral bioavailability of Miconazole is low (25-30%) because there is little absorption of Miconazole from the intestinal tract. Miconazole is systemically absorbed after administration as the oral gel. Absorbed Miconazole is bound to plasma proteins (88.2%), primarily to serum albumin and red blood cells (10.6%). The absorbed portion of Miconazole oral gel is largely metabolized; less than 1% of the administered dose is excreted unchanged in the urine. The terminal plasma half-life is 20-25 hours in most patients. The elimination half-life of Miconazole is similar in any renal impaired patient.</p>