Terconazole clinical pharmacology
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmed Zaghw, M.D. [2]
Clinical Pharmacology
Following intravaginal administration of terconazole in humans, absorption ranged from 5–8% in three hysterectomized subjects and 12–16% in two non-hysterectomized subjects with tubal ligations.
Following daily intravaginal administration of 0.8% terconazole 40 mg (0.8% cream × 5 g) for seven days to normal humans, plasma concentrations were low and gradually rose to a daily peak (mean of 5.9 ng/mL or 0.006 mcg/mL) at 6.6 hours.
Results from similar studies in patients with vulvovaginal candidiasis indicate that the slow rate of absorption, the lack of accumulation, and the mean peak plasma concentration of terconazole was not different from that observed in healthy women. The absorption characteristics of terconazole 0.8% in pregnant or non-pregnant patients with vulvovaginal candidiasis were also similar to those found in normal volunteers.
Following oral (30 mg) administration of 14C-labelled terconazole, the harmonic half-life of elimination from the blood for the parent terconazole was 6.9 hours (range 4.0–11.3). Terconazole is extensively metabolized; the plasma AUC for terconazole compared to the AUC for total radioactivity was 0.6%. Total radioactivity was eliminated from the blood with a harmonic half-life of 52.2 hours (range 44–60). Excretion of radioactivity was both by renal (32–56%) and fecal (47–52%) routes.
In vitro, terconazole is highly protein bound (94.9%) and the degree of binding is independent of drug concentration.
Photosensitivity reactions were observed in some normal volunteers following repeated dermal application of terconazole 2.0% and 0.8% creams under conditions of filtered artificial ultraviolet light.
Photosensitivity reactions have not been observed in U.S. and foreign clinical trials in patients who were treated with terconazole suppositories or vaginal cream (0.4% and 0.8%).[1]
References
Adapted from the FDA Package Insert.