New moms have a lot to worry about, and if you come down with an infection that needs treatment, you may wonder if metronidazole and breastfeeding are safe together. If you are breastfeeding, your baby may be exposed to this antibiotic through your breastmilk. This article answers the question whether metronidazole is considered safe during breastfeeding, explains why it may be used during breastfeeding, and things to watch out for.

Is It Okay if I Take Metronidazole While Breastfeeding?

Metronidazole is often needed for certain infections and your doctor will decide if the benefits of using the drug outweigh the risk. If necessary, you may be advised to stop breastfeeding during treatment. This also depends on the route of administration. Here are the precautions for how this drug is used:

1)    Oral

Oral metronidazole is excreted into breast milk. If your doctor wants to prescribe this medication to be taken by mouth, let them know you are breastfeeding. It is not recommended due to side-effects noted in breastfeeding infants of mothers taking this drug.

The Centers for Disease Control (CDC) recommend that if you need oral metronidazole and breastfeeding is your only feeding option, then breastfeeding should be stopped for 24 hours. You will need to use supplemental formula during this time. Your doctor may give you the medication in a single dose, then you can start breastfeeding 24 hours after the drug is taken.

Keep in mind that studies show metronidazole is still found in small amounts in breast milk for up to 48 hours.

2) Intravenous

For serious infections, your doctor may need to put you on an intravenous dose of metronidazole. This will deliver the medication directly into your bloodstream. Breastfeeding is not recommended while on the IV form of this medication, because of the amount that may be passed into breast milk.

3) Vaginal Gel

If you are prescribed metronidazole vaginal gel, let your doctor know that you are breastfeeding. Research shows that not as much of the topical gel is absorbed systemically as the oral form. Most doctors and pharmacists agree that this use is safe. However, follow your doctor’s advice when deciding what to do. Literature also states that breastfeeding should be discontinued until 24 hours after your last dose of this medication. If you decide to do this, you will need to use supplemental formula during treatment.

Uses for Metronidazole During Breastfeeding

Here are some of the common illnesses metronidazole is used for: 

  • Bacterial Vaginosis

This is a common vaginal infection caused by the overgrowth of “bad” bacteria in the vagina. Bacterial vaginosis is common after the birth of a baby due to changes in the vaginal flora.

Symptoms include fishy odor, gray-ish discharge, burning, itching, or you may have no symptoms.

  • Trichomonas Vaginitis

Trichomonas vaginitis is a parasite that is sexually transmitted. After having sex with an infected partner, symptoms show up within 5 to 28 days. Both partners need to be treated to prevent reinfection, and metronidazole is usually the “drug of choice” for this infection.

Symptoms include burning with urination, vaginal itching, gray or green discharge, and foul odor.

  • Uterine Infections

One very serious reason you may need metronidazole and breastfeeding may be an issue, is if you develop an infection in your uterus soon after childbirth. If you acquire a bacterial infection in your uterus after delivery, metronidazole is usually given intravenously. The doctor will most likely recommend that you supplement your baby with formula during treatment.

Symptoms of a uterine infection include abdominal pain, elevated temperature and discharge from the vagina with an odor.

  • Pelvic Inflammatory Disease

Pelvic inflammatory disease is an invasive infection that affects the female reproductive organs. It usually begins with a bacterial infection, and is often a sexually transmitted disease that has been left untreated. The infection moves up through the vagina, into the cervix, then invades the uterus and fallopian tubes. This infection is often treated with metronidazole and may cause issues with breastfeeding.

Symptoms include pelvic pain, abdominal pain, discharge, and fever. 

  • Intestinal Infections

There is an intestinal infection known as clostridium difficile that requires treatment with metronidazole. This infection often happens after treatment with antibiotics. The “good” bacteria in the intestines are destroyed by antibiotics, which can cause c.diff to take over. This is a severe infection and highly contagious. Metronidazole must be taken orally to eradicate the bacteria.

Symptoms include watery diarrhea, abdominal pain, sour/foul odor to stools, and possible bloody diarrhea.

Tips for Using Metronidazole While Breastfeeding

If you need to take metronidazole while breastfeeding, here are some tips to help keep you and your baby healthy:

Pump Your Milk

If you need to stop breastfeeding, pump your milk during treatment and discard. This will help clear your milk of any medication, and keep your supply up for your baby.

Ask About Alternatives

Ask your doctor about taking an alternative antibiotic, if possible. Alternative antibiotics include:

  • Vancomycin
  • Amoxicillin
  • Ampicillin 
  • Clindamycin
  1. Watch For Side-Effects

While they say less than 10 to 20 percent enters breast milk, your baby may have side-effects when you return to nursing. These may include intolerance to lactose, diarrhea, and candida infection (thrush). You may also notice candida on the buttocks, in the form of a rash.

  1. Eat Yogurt

To prevent candida in you and your baby, make sure you eat yogurt while taking this medication. This will help replace the “good” bacteria in your body and improve your body’s ability to fight off infection.

  1. Drink Extra Fluids

If you are taking metronidazole and breastfeeding at the same time, increase your fluid intake during treatment. This will help prevent too much medication from going into your milk. Even if you stop nursing during treatment, this will help the medication pass from your system faster.