Secnidazole: uses, dosing, side effects & brands
Secnidazole is a medicine sold in the U.S. under one brand, for bacterial vaginosis. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats
- Bacterial Vaginosis
- Available as
- Powder
- Sold as
- Solosec
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How secnidazole is dosed
From the FDA label for Solosec (application NDA209363). Other secnidazole products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Bacterial Vaginosis (female patients 12 years of age and older): Administer a single 2-gram packet of granules once orally, without regard to the timing of meals. ( 2.1 ) Trichomoniasis (patients 12 years of age and older): Administer a single 2-gram packet of granules once orally, without regard to the timing of meals. Treat sexual partners with the same dose and at the same time. ( 2.2 ) Sprinkle entire contents of packet onto applesauce, yogurt or pudding and consume all of the mixture within 30 minutes without chewing or crunching the granules. A glass of water may be taken after the administration of SOLOSEC to aid in swallowing. ( 2.3 ) SOLOSEC is not intended to be dissolved in any liquid. ( 2.3 ) 2.1 Recommended Dosage for Bacterial Vaginosis The recommended dosage of SOLOSEC for the treatment of bacterial vaginosis in female patients 12 years of age and older is a single 2-gram packet of granules taken once orally, without regard to the timing of meals [see Clinical Pharmacology (12.3) ] . 2.2 Recommended Dosage for Trichomoniasis The recommended dosage of SOLOSEC for the treatment of trichomoniasis in patients 12 years of age and older is a single 2-gram packet of granules taken once orally, without regard to the timing of meals [see Clinical Pharmacology (12.3) ] . Since trichomoniasis is a sexually transmitted disease, treat sexual partners with the same dose and…
Secnidazole side effects
The following important adverse reactions are discussed in greater detail in other sections of labeling: Vulvovaginal Candidiasis [Warnings and Precautions (5.1)] Bacterial Vaginosis : Most common adverse reactions observed in clinical trials of bacterial vaginosis (incidence ≥ 2%) were vulvovaginal candidiasis, headache, nausea, dysgeusia, vomiting, diarrhea, abdominal pain, and vulvovaginal pruritus. ( 6.1 ). Trichomoniasis : Most common adverse reaction observed in the clinical trial of trichomoniasis (incidence ≥ 2%) was vulvovaginal candidiasis. ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Evofem at toll-free-phone 1-833-EVFMBIO (1-833-383-6246) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Bacterial Vaginosis The safety data described below reflect exposure to 629 patients, of whom 558 received a 2 g dose of SOLOSEC. SOLOSEC was evaluated in four clinical trials of female patients diagnosed with bacterial vaginosis: two placebo-controlled trials (Trial 1 n=215, Trial 2 n=189) and two uncontrolled safety trials (Trial 3 n=321, Trial 4 n=40). Most Common Adverse…
Who shouldn’t take secnidazole
SOLOSEC is contraindicated: In patients who have shown hypersensitivity to secnidazole, or other nitroimidazole derivatives. In patients with Cockayne syndrome: Severe irreversible hepatotoxicity/acute liver failure with fatal outcomes have been reported after initiation of metronidazole, another nitroimidazole drug, structurally related to secnidazole, in patients with Cockayne syndrome [see Adverse Reactions (6.2) ] . History of hypersensitivity to secnidazole, or other nitroimidazole derivatives. ( 4 ) Patients with Cockayne syndrome. ( 4 , 6.2 )
Secnidazole drug interactions
7.1 Oral Contraceptives There was no clinically significant drug interaction between secnidazole and the combination oral contraceptive, ethinyl estradiol plus norethindrone [see Clinical Pharmacology (12.3) ] . SOLOSEC can be co-administered with combination oral contraceptives (e.g., ethinyl estradiol plus norethindrone). 7.2 Alcohol Alcoholic beverages and preparations containing ethanol or propylene glycol should be avoided during SOLOSEC therapy and for 2 days after treatment is stopped. Nausea, vomiting, diarrhea, abdominal pain, dizziness, and headache have been reported when SOLOSEC was taken concomitantly with alcohol [see Dosage and Administration (2.3) , Adverse Reactions (6.2) and Clinical Pharmacology (12.3) ] .
Every secnidazole product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Solosec.
Secnidazole and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for secnidazole: levels in milk, effects in breastfed infants, and the drugs it would consider insteadNo information is available on the clinical use of secnidazole during breastfeeding and no studies have evaluated adverse effects of secnidazole on the infant during breastfeeding, but presumably they are similar to those of the closely related drug, metronidazole, such as increased risk of oral and rectal Candida infections.
National Institute of Child Health and Human Development, record revised August 16, 2021. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about secnidazole
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 56 reports naming secnidazole, and the FDA flagged 93% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- foetal exposure during pregnancy10 reports
- developmental hip dysplasia8 reports
- micrognathia8 reports
- talipes8 reports
- skull malformation7 reports
- premature delivery6 reports
- pyrexia6 reports
- congenital knee deformity5 reports
Read these as a signal, not a rate. A report does not mean secnidazole caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 26, 2026.
Related calculators
Frequently asked questions
What is secnidazole?
The active ingredient in SOLOSEC Oral Granules is secnidazole (also named 1-(2-hydroxypropyl)-2-methyl-5-nitroimidazole and 1-(2-methyl-5-nitro-1 H -imidazol-1-yl) propan-2-ol), a nitroimidazole antimicrobial.
Can you take secnidazole with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run secnidazole against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does secnidazole come in?
Across the brands we track, secnidazole is currently marketed as powder, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic secnidazole?
We do not currently list a generic-labelled secnidazole product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Secnidazole: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/secnidazole
- MLA
- “Secnidazole: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/secnidazole.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for secnidazole on DailyMed (NIH) ↗.