Antibiotics for Bacterial Vaginosis (BV)
- Best antibiotics for BV
- Metronidazole (Flagyl®, MetroGel®)
- Clindamycin (Cleocin®)
- Tinidazole (Tindamax®)
- Secnidazole (Solosec®)
- Less Effective and Ineffective Antibiotics
Based on "Principles and Practice of Infectious Diseases"
written by John E. Bennett, MD
Updated according to Sexually Transmitted Diseases Treatment Guidelines by CDC2.
What is Bacterial Vaginosis?
Bacterial Vaginosis (BV) is a form of vaginitis, and represents vaginal inflammatory response to microbial colonization and altered pH.
This polymicrobial syndrome occurs when normal protective vaginal bacterial flora is replaced with of anaerobic bacteria including Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis, Prevotella species, Mobiluncus species, and other BV-associated bacteria. The condition is accompanied by a rise in vaginal pH and increased amines which produce odor.
BV is often associated with the STIs, including chlamydia, gonorrhea, herpes.
Best Antibiotics for BV 2
- Metronidazole oral tablets
- Metronidazole gel
- Clindamycin cream
Potential benefits of BV treatment include:
- Reduction of the risk for acquiring sexually transmitted infections, including C. trachomatis, N. gonorrhoeae, T. vaginalis, genital herpes
- Reduced threat to reproductive health
- Reduced risk of preterm delivery
All first line antibiotics (oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream) are nearly equally effective treatments for bacterial vaginosis1.
As all recommended treatments provide almost the same cure rates the choice of the best and most suitable medication should consider additional factors such as side effects, risk of BV recurrence, drug availability, specific patient health history (e.g. allergic reactions).
Metronidazole is the most common BV treating medication.
- Very effective: high cure rate.
- Metronidazole is highly active against anaerobic bacteria.
- Various preparations allow vaginal or oral administration.
- This antibiotic is inexpensive.
- Metronidazole is less harmful for lactobacilli than clindamycin.
- Metronidazole may be used for BV during pregnancy2.
- Frequently causes unpleasant gastrointestinal side effects, including metallic taste in the mouth, nausea, vomiting, yeast infection.
Metronidazole oral tablets (Flagyl®) dosage for BV: 500 mg twice daily for 7 days.
Alternative regimen: 2 g of metronidazole as a single dose.
Metronidazole vaginal gel (MetroGel®, Vandazole®) dosage for BV: one full applicator intravaginally, once a day for 5 days.
Clindamycin is another recommended first line antimicrobial medication for treatment of BV.
- Clindamycin is available in various formulations, including vaginal (cream and suppositories) and oral.
- Clindamycin is more potent than metronidazole against bacteria causing BV.
- Oral clindamycin may be used for BV during pregnancy2.
- Clindamycin ovules contain ingredients that weaken latex condoms.
- Clindamycin cream is an expensive treatment.
- Clindamycin is not usually recommended as a preventive treatment for recurrent BV.
- Oral clindamycin carries a high risk of diarrhea.
Clindamycin vaginal cream (Clindesse®) dosage: one full applicator intravaginally at bedtime for 7 days.
Oral clindamycin and suppositories are recommended as alternative second-line choices.
Clindamycin oral capsules (Cleocin®) dosage for BV: 300 mg twice daily for 7 days.
Clindamycin phosphate vaginal suppositories (Cleocin® vaginal ovules) dosage for BV: 100 mg intravaginally once at bedtime for 3 days.
Tinidazole is bactericidal against anaerobic bacteria.
- High cure rates.
- Shorter course of oral antibiotic therapy than with metronidazole.
- Better tolerability - tinidazole generally causes fewer side effects.
- Tinidazole is more expensive than metronidazole.
- Tinidazole should be avoided during pregnancy.
Tinidazole dosage for BV: 2 g once daily for 2 days or 1 g once daily for 5 days.
Secnidazole (Solosec®) is the newest nitroimidazole antibiotic for BV. The medicine was approved by the FDA for treatment of bacterial vaginosis in September, 2017.
- High cure rates.
- Very convenient single-dose oral regimen.
- Secnidazole is particularly good choice for women with doubtful compliance.
- No alcohol warning.
- As most new medications secnidazole is more expensive than metronidazole or tinidazole.
Secnidazole dosage for BV: single 2 g oral dose.
- Nifuratel has beneficial antimicrobial spectrum - it is highly active against G. vaginalis and A. vaginae and doesn’t affect lactobacilli 3.
- May provide higher cure rate in women with bacterial vaginosis and mixed bacterial flora4.
- Nifuratel is not approved in U.S.
Nifuratel dosage for BV: 250-500 mg intravaginally for 10 days.
List of antibiotics that should NOT be used to treat BV:
- Azithromycin, erythromycin
- Doxycycline, tetracycline
- Ampicillin, amoxicillin
- Triple-sulfa vaginal creams
- 1. Ferris DG, Litaker MS, Woodward L, Mathis D, Hendrich J. Treatment of bacterial vaginosis: a comparison of oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream. J Fam Pract. 1995 Nov;41(5):443-9.
- 2. CDC Sexually Transmitted Diseases Treatment Guidelines: Diseases Characterized by Vaginal Discharge Bacterial Vaginosis
- 3. Togni G, Battini V, Bulgheroni A, Mailland F, Caserini M, Mendling W. In vitro activity of nifuratel on vaginal bacteria: could it be a good candidate for the treatment of bacterial vaginosis? Antimicrob Agents Chemother. 2011 May; 55(5):2490-2.
- 4. Mendling W, Poli A, Magnani P. Clinical effects of nifuratel in vulvovaginal infections. A meta-analysis of metronidazole-controlled trials. Arzneimittelforschung. 2002;52(10):725-30.
Published: May 18, 2018
Last updated: July 03, 2018