Secnidazole is an oral nitroimidazole antimicrobial indicated for the treatment of bacterial vaginosis and trichomoniasis in adults and pediatric patients 12 years and older. Sexual partners should be simultaneously treated for trichomoniasis to avoid reinfection. Secnidazole is approved as single-dose therapy. It was found to be at least as effective as a 7-day course of metronidazole for bacterial vaginosis. In a double-dummy, double-blind, noninferiority study (n = 577), therapeutic success, a composite of clinical and bacteriological cure, rates at day 28 were similar, 60.1% and 59.5% for single-dose secnidazole vs. multiple-dose metronidazole (500 mg PO twice daily for 7 days), respectively. For trichomoniasis, secnidazole had cure rates ranging from 91.7% to 100%. Single-dose therapy increases convenience and promotes compliance.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Oral Administration
Other Oral Formulations
Oral granules
-May be taken without regard to meals.
-Sprinkle the entire contents of the secnidazole packet onto applesauce, yogurt, or pudding; the granules will not dissolve.
-Granules are not intended to be dissolved in any liquid.
-Do not chew or crunch the granules.
-Consume the entire mixture within 30 minutes.
-A glass of water may be taken after administration to aid in swallowing.
The use of secnidazole may result in vulvovaginal candidiasis. In clinical trials, vulvovaginal candidiasis occurred in 2.7% to 9.6% of patients who received secnidazole. Symptomatic vulvovaginal candidiasis may require treatment with an antifungal agent. Vulvovaginal pruritus (vaginitis) was also reported in 2% of secnidazole-treated patients vs. 1.5% of placebo-treated patients.
Gastrointestinal adverse events reported during clinical trials with secnidazole include nausea (3.6% to 5.3%), diarrhea (2.5%), abdominal pain (2%), vomiting (2.5%), and dysgeusia (3.4%). One patient in trichomoniasis trials discontinued secnidazole due to nausea and productive cough.
Headache was reported in 3.6% of secnidazole-treated patients during clinical trials.
Severe, irreversible hepatotoxicity and acute hepatic failure have been reported in patients with Cockayne syndrome that have been treated with systemic metronidazole, another nitroimidazole agent, structurally related to secnidazole. Some of these cases have been fatal with rapid onset after therapy initiation; latency from drug start to signs of liver failure have been as short as 2 days.
Secnidazole is contraindicated in patients with known secnidazole hypersensitivity or hypersensitivity to other ingredients of the formulation or nitroimidazole derivatives.
Avoid chronic use of secnidazole. Neoplastic disease affecting the liver, lungs, mammary, and lymphatic tissues has been associated with chronic use of nitroimidazole derivatives, which are structurally related to secnidazole, in mice and rats. It is unclear if the positive tumor findings in lifetime rodent studies of these nitroimidazoles demonstrate a risk to a patient taking a single dose of secnidazole to treat bacterial vaginosis.
Secnidazole is contraindicated in patients with Cockayne syndrome. Cases of severe irreversible hepatotoxicity and acute hepatic failure, including fatal outcomes with very rapid onset, have been reported in these patients after treatment initiation with systemic metronidazole, another nitroimidazole agent, structurally related to secnidazole. The latency period from starting metronidazole to signs of liver failure was as short as 2 days.
Limited available data with secnidazole use during human pregnancy are insufficient to inform a drug-associated risk of adverse developmental outcomes. Animal data show no evidence of adverse developmental outcomes at doses up to 4 times the clinical dose; however, maternal toxicity was observed.
Because of the potential for serious adverse reactions, including tumorigenicity, breast-feeding is not recommended during treatment with secnidazole and for 96 hours after its administration. Breast-feeding mothers may choose to pump and discard breast milk during this time and feed infants stored human milk or formula. Although there is no information on the presence of secnidazole in human milk, the effects on the breast-fed child, or the effects on milk production, other nitroimidazole derivatives are present in human milk.
Per the manufacturer, this drug has been shown to be active against most strains of the following microorganisms either in vitro and/or in clinical infections: Bacteroides sp., Gardnerella vaginalis, Megasphaera-like type 1, Megasphaera-like type 2, Mobiluncus sp., Prevotella sp., Trichomonas vaginalis
NOTE: The safety and effectiveness in treating clinical infections due to organisms with in vitro data only have not been established in adequate and well-controlled clinical trials.
For the treatment of bacterial vaginosis:
Oral dosage:
Adults: 2 g PO as a single dose as an alternative.
Children and Adolescents 12 to 17 years: 2 g PO as a single dose as an alternative.
For the treatment of trichomoniasis:
Oral dosage:
Adults: 2 g PO as a single dose. Treat sexual partners concurrently with the same dose to prevent reinfection.
Children and Adolescents 12 to 17 years: 2 g PO as a single dose. Treat sexual partners concurrently with the same dose to prevent reinfection.
Maximum Dosage Limits:
-Adults
2 g PO.
-Geriatric
2 g PO.
-Adolescents
2 g PO.
-Children
12 years: 2 g PO.
1 to 11 years: Safety and efficacy have not been established.
-Infants
Safety and efficacy have not been established.
-Neonates
Safety and efficacy have not been established.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
Ethanol: (Major) Advise patients to discontinue alcohol-containing beverages and other forms of alcohol (including medicines with significant alcohol content and any products containing propylene glycol) before, during, and up to 2 days after therapy with secnidazole. Side effects, including nausea, vomiting, diarrhea, abdominal pain, dizziness, and headache, may occur if used together. (Moderate) Although the injection of alcohol used for therapeutic procedures is not expected to produce significant systemic effects of ethanol, use caution with concomitant use of secnidazole. Disulfiram-like side effects, including nausea, vomiting, tachycardia, headache, flushing, and abdominal cramps, may occur.
Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Major) Prior or concomitant use of antibiotics with sodium picosulfate; magnesium oxide; anhydrous citric acid may reduce efficacy of the bowel preparation as conversion of sodium picosulfate to its active metabolite bis-(p-hydroxy-phenyl)-pyridyl-2-methane (BHPM) is mediated by colonic bacteria. If possible, avoid coadministration. Certain antibiotics (i.e., tetracyclines and quinolones) may chelate with the magnesium in sodium picosulfate; magnesium oxide; anhydrous citric acid solution. Therefore, these antibiotics should be taken at least 2 hours before and not less than 6 hours after the administration of sodium picosulfate; magnesium oxide; anhydrous citric acid solution.
Secnidazole is a nitroimidazole antimicrobial. It enters the bacterial and Trichomonas cells where the nitro group is reduced by nitroreductase enzyme(s). This leads to the production of radical anions and a series of intermediates, depletion of thiols, DNA damage, and death of susceptible isolates. These radical anions may interfere with bacterial DNA synthesis of susceptible isolates.
Bacterial and T. vaginalis isolates with reduced in vitro susceptibility to metronidazole also show reduced susceptibility to secnidazole. The mechanism of resistance, like for other nitroimidazoles, appears to be multifactorial and includes decreased uptake of the drug, higher efflux activity, and/or altered nitroreductase activity.
Secnidazole is administered orally. The plasma protein binding of secnidazole is less than 5%. The apparent volume of distribution is approximately 42 L.
Secnidazole is metabolized in vitro via oxidation by the human hepatic CYP450 enzyme system with up to 1% converted to metabolites. The total body clearance of secnidazole is approximately 25 mL/minute with a renal clearance of approximately 3.9 mL/minute. Approximately 15% of the 2 g oral dose is excreted unchanged in the urine. The elimination half-life of secnidazole is approximately 17 hours.
Affected cytochrome P450 isoenzymes and drug transporters: none
In vitro metabolism studies with secnidazole demonstrate that there is minimal potential for interactions with CYP450 substrates, inhibitors, or inducers.
-Route-Specific Pharmacokinetics
Oral Route
After a single, oral secnidazole 2 g dose mixed in 4 ounces of applesauce, mean Cmax was 45.4 mcg/mL and mean AUC was 1331.6 mcg x hour/mL. The median time to peak concentration (Tmax) was 4 hours. There were no differences in Cmax, AUC, or Tmax when secnidazole was mixed with pudding or yogurt compared to applesauce. Additionally, administration of secnidazole 2 g admixed with applesauce after a high-fat meal resulted in no significant differences in Cmax or AUC compared with fasted conditions.