What medications can cause breast milk to dry up?

October 12, 2025 •

5 min read

An estimated 90% of mothers are concerned about the effects of medication on their breast milk supply and their infant's health. Understanding what medications can cause breast milk to dry up is crucial for nursing parents needing to manage illness or use contraception without jeopardizing their lactation journey. Certain common over-the-counter and prescription drugs, along with some herbal remedies, are known to suppress milk production by interfering with the hormones responsible for lactation.

Quick Summary

This article details various medications that can reduce or stop breast milk production, including decongestants like pseudoephedrine, hormonal contraceptives containing estrogen, and certain prescription drugs. It explains their mechanisms of action, potential side effects for both mother and baby, and lists safe alternative options for managing health concerns while protecting lactation.

Key Points

Decongestants: Oral pseudoephedrine (Sudafed) is known to significantly reduce breast milk supply, especially with repeated use.
Hormonal Birth Control: Combined contraceptives containing estrogen can suppress lactation and are not recommended for the first 4-6 weeks postpartum.
Dopamine Agonists: Prescription drugs like bromocriptine actively suppress prolactin and are not routinely used for lactation suppression due to safety risks.
Certain Antihistamines: Older, sedating antihistamines (like Benadryl) with anticholinergic effects can potentially decrease milk supply and should be used with caution.
Some Herbal Remedies: Herbs such as sage and peppermint are traditional anti-galactagogues that can reduce milk production if consumed in significant quantities.
Consult a Doctor: Always discuss any medication, including OTC and herbal products, with a healthcare provider to ensure safety for both mother and baby.

How Lactation Works

To understand how certain drugs affect milk supply, it's helpful to know the basics of lactation. Breast milk production is regulated by a delicate balance of hormones, primarily prolactin and oxytocin. Prolactin is responsible for milk synthesis in the mammary glands, while oxytocin triggers the 'letdown reflex' that releases milk. Medications that interfere with either of these hormones or affect the body's fluid balance can lead to a noticeable drop in milk production.

Over-the-Counter Medications

Many people don't realize that some readily available over-the-counter (OTC) drugs can significantly impact lactation. Awareness is key to making informed decisions, particularly during a cold or allergy season.

Decongestants

One of the most well-documented culprits for decreasing milk supply is the oral decongestant pseudoephedrine (Sudafed).

Mechanism: Pseudoephedrine acts by constricting blood vessels. Studies have shown that even a single 60 mg dose can reduce milk production by 24% over 24 hours. This effect is believed to be linked to a reduction in serum prolactin levels.
Effect on lactation: Significant and rapid decrease in milk volume, especially in mothers with not-yet-established lactation or those with a delicate supply.
Safe alternatives: Nasal sprays containing oxymetazoline (Afrin) are generally preferred as a safer alternative for short-term use, as they have minimal systemic absorption.

Antihistamines

Antihistamines are another class of OTC medications that can affect milk supply, although the impact can vary.

First-generation (sedating) antihistamines: Drugs like diphenhydramine (Benadryl) have anticholinergic properties that can potentially reduce milk production, especially with prolonged or high-dose use. They can also cause drowsiness in both the mother and baby.
Second-generation (non-sedating) antihistamines: Newer antihistamines such as loratadine (Claritin) and cetirizine (Zyrtec) have minimal or no anticholinergic activity and are less likely to impact milk supply.

Hormonal Contraceptives

Breastfeeding mothers often need reliable birth control, but not all options are suitable. Combined hormonal contraceptives containing estrogen are a major concern for suppressing milk production.

Combination birth control

Mechanism: Estrogen interferes with the action of prolactin, the primary hormone for milk production. The effect is often dose-dependent, with higher doses causing a more pronounced reduction.
Effect on lactation: Can lower milk supply, particularly if introduced before lactation is well-established (usually 4–6 weeks postpartum). The American College of Obstetricians and Gynecologists (ACOG) recommends waiting at least six weeks after childbirth before starting a combined hormonal contraceptive.
Safe alternatives: Progestin-only contraceptives, including the mini-pill, hormonal IUDs, injections, or implants, do not contain estrogen and are generally considered safe for milk supply. Non-hormonal barrier methods like condoms are also excellent options.

Prescription Medications and Hormonal Agents

Several prescription drugs can also negatively affect lactation, though they are usually reserved for specific medical conditions or for intentional lactation suppression.

Dopamine Agonists

Mechanism: Dopamine agonists, such as bromocriptine (Parlodel) and cabergoline, suppress prolactin secretion by mimicking the effects of the neurotransmitter dopamine.
Effect on lactation: These drugs are potent inhibitors of lactation and were historically used to suppress milk production after childbirth. However, bromocriptine is no longer recommended for routine lactation suppression due to the risk of serious maternal side effects, including heart attack, stroke, and seizures. Cabergoline may be used in specific, medically-supervised cases for oversupply or lactation cessation.

Diuretics

Mechanism: Diuretics increase urination to remove excess fluid from the body. Higher doses can impact overall fluid balance, potentially reducing milk volume.
Effect on lactation: While low doses of thiazide diuretics like hydrochlorothiazide are compatible with breastfeeding, high doses have been used in the past to suppress lactation. Close monitoring of milk supply is necessary when taking these medications.

Herbal Remedies

Some mothers turn to natural remedies, but certain herbs can also decrease milk supply.

Sage: Sage contains anti-galactagogue properties and is traditionally used to dry up milk.
Peppermint: Peppermint, especially in high concentrations like peppermint oil or strong tea, is known to be an anti-galactagogue.
Parsley: Similar to sage and peppermint, consuming large amounts of parsley may have a negative effect on milk supply.

Comparison of Medications Affecting Milk Supply


Medication Type	Examples	Mechanism	Impact on Milk Supply	Breastfeeding Recommendations	Safe Alternatives
Decongestants	Pseudoephedrine (Sudafed)	Reduces prolactin secretion, constricts vessels	Significant decrease	Use with caution, especially with low supply; short-term only	Oxymetazoline nasal spray
Hormonal Contraceptives	Combined Pill, Patch, Ring	Estrogen interferes with prolactin	Can decrease, especially if initiated early	Postpone 4-6 weeks postpartum; monitor supply closely	Progestin-only methods (mini-pill, IUD)
Antihistamines (First-Gen)	Diphenhydramine (Benadryl)	Anticholinergic effects	Potential for decrease with high/long-term use	Use sparingly; observe for infant drowsiness	Second-gen antihistamines (loratadine)
Dopamine Agonists	Bromocriptine, Cabergoline	Suppresses prolactin secretion	Strong inhibitory effect	Not for routine suppression; caution advised for other uses	Non-pharmacological cessation methods
Diuretics (High Dose)	Hydrochlorothiazide (high dose)	Affects fluid balance	Potential for decrease	Monitor supply; low doses generally compatible	Low-dose diuretics if needed; non-drug measures
Herbal Remedies	Sage, Peppermint	Anti-galactagogue properties	Can decrease, dependent on dosage	Avoid high intake; monitor for effect on supply	N/A

The Importance of Consultation

Navigating medication use while breastfeeding requires a personalized approach. It is crucial to consult with healthcare providers, including your doctor and a lactation specialist, before taking any medication, whether OTC, prescription, or herbal. They can help you weigh the risks and benefits, determine appropriate dosing, and recommend safer options based on your individual health needs and your baby's age and health status. The American Academy of Pediatrics advises using the lowest effective dose for the shortest duration necessary to minimize any potential impact on your milk supply and your infant.

Conclusion

Several medications have the potential to decrease or completely dry up breast milk, ranging from common cold remedies like pseudoephedrine to hormonal contraceptives and prescription drugs such as dopamine agonists. The impact depends on the specific drug, dosage, and duration of use, as well as the timing relative to the establishment of lactation. By being aware of these potential effects and consulting with healthcare professionals, breastfeeding mothers can make informed decisions to protect their milk supply while effectively managing their health.

Authoritative Resource Link

For more information on the safety of medications during lactation, refer to the Drugs and Lactation Database (LactMed) provided by the National Institutes of Health (NIH): LactMed - National Library of Medicine

Frequently Asked Questions

Not always, but pseudoephedrine is a known lactation suppressant that can decrease milk supply by as much as 24% after a single dose. Its effect is more pronounced during the early postpartum period or in mothers with an already low supply. Safer alternatives like saline nasal spray or nasal sprays containing oxymetazoline are often recommended.

Progestin-only hormonal contraceptives, such as the mini-pill, hormonal IUDs, injections (Depo-Provera), or implants, are preferred for breastfeeding mothers. They do not contain estrogen, which can lower milk supply. Non-hormonal options like barrier methods or the copper IUD are also excellent choices.

Yes, high doses of diuretics have been shown to cause a reduction in milk volume. However, typical low doses used to treat conditions like hypertension are generally considered compatible with nursing, though monitoring milk supply is recommended.

No, not all antihistamines affect milk supply in the same way. First-generation (sedating) antihistamines, like diphenhydramine (Benadryl), can potentially decrease milk production, while second-generation (non-sedating) antihistamines like loratadine (Claritin) and cetirizine (Zyrtec) are much less likely to cause an issue.

Bromocriptine is no longer recommended for routine lactation suppression in many countries, including the U.S., due to the risk of serious side effects such as stroke, heart attack, and seizures. Its use is restricted to rare, medically supervised cases.

Herbs like sage and peppermint have anti-galactagogue properties and can decrease milk production. The effect is often dose-dependent, so a small amount used in cooking is unlikely to cause a problem, but concentrated teas or oils can have a significant impact.

To minimize risk, always consult a healthcare provider. They can advise you to take the lowest effective dose for the shortest period necessary. You can also time your doses, taking them immediately after a feeding or before your baby's longest sleep period to reduce infant exposure.