Drug Levels and Effects:

Summary of Use during Lactation:

Anise (Pimpinella anisum) seeds contain anethole, which is a phytoestrogen. Anise is a purported galactogogue,[1][2][3][4][5][6] and is included in some proprietarymixturespromoted to increase milk supply; however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[7] Maternal anise ingestion reportedly imparts an odor to breastmilk,[8] possibly because anethole is excreted into breastmilk.[9] Anise is "generally recognized as safe" (GRAS) as a flavoring by the US Food and Drug Administration. Excessive maternal use of an herbal tea containing anise and other herbs appeared to cause toxicity in two breastfed newborns, consistent with toxicity caused by anethole.

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Drug Levels:

Maternal Levels.

Eighteen lactating women were given 100 mg of trans-anethol in a capsule on 3 test days. Milk samples were collected every 2 hours for 8 hours starting at the time of ingestion. Trans-anethol was detected in milk at all collection times, with the average concentrations of 2 mcg/L at 0 hours, 9.9 mcg/L at 2 hours, 9.2 mcg/L at 4 hours, 7.3 mcg/L at 6 hours and 4.3 mcg/L at 8 hours after the dose. The average peak anenthol concentration in milk was 23.2 mcg/L. Only small amounts of anenthol glucuronide metabolites were present in the milk samples.[9]

Infant Levels.

Relevant published information was not found as of the revision date.

Effects in Breastfed Infants:

Two breastfed infants, aged 15 and 20 days, were admitted to the hospital for a reported lack of weight gain in the previous 7 to 10 days, caused by "difficult feeding". The parents reported restlessness and vomiting during the past day. One of the mothers also reported feeling drowsy and weak. On examination, the infants were afebrile but had hypotonia, lethargy, emesis, weak cry, poor sucking and weak responses to painful stimuli. Infant laboratory values, electrocardiograms and blood pressures were normal, and septic work-ups were negative. Both mothers had both been drinking more than 2 liters daily of an herbal teamixturereportedly containing licorice, fennel, anise, and goat's rue to stimulate lactation. After the mothers discontinued breastfeeding and the herbal tea, the infants improved within 24 to 36 hours. Symptoms of the affected mother also resolved rapidly after discontinuing the herbal tea. After 2 days, breastfeeding was reinstituted with no further symptoms in the infants. Both infants were doing well at 6 months of age. The authors attributed the maternal and infant symptoms to anethole, which is found in both anise and fennel; however, the anethole levels were not measured in breastmilk, nor were the teas tested for their content.[10]

Possible Effects on Lactation:

A group of 5 nursing mothers were given no herb for 5 days, 15 mL of a 5% infusion of anise 3 times daily for 10 days, followed by another 5-day control period from days 15 to 20. Their diet and environment were kept constant during the study period. Milk volume was measured daily and milk fat percentage was measured on days 5, 10, 15 and 20. The increase in milk volume was variable, from substantial increases to no effect to decreases in volume at the end of the study period. No overall changes in milk fat were observed.[11] Because of the lack of randomization, blinding and controls, and small number of participants, no valid conclusion can be made from this study on the galactagogue effects of anise.

In an uncontrolled, nonblinded study, 5 nursing mothers were given 4 cups of anise tea (preparation method not stated) daily to determine if milk production was improved. The measured endpoint was duration of lactation in the current pregnancy compared to the previous pregnancy based on maternal reporting. Treated women had trivial increases in duration of lactation from 10 days in the previous pregnancy to 15 days with use of the tea.[12] Because of the faulty study design and small number of participants, no valid conclusion can be made from this study on the galactagogue effects of anise.


1. Yarnell E . Botanical medicine in pregnancy and lactation. Altern Complement Ther. 1997;3 (April):93-100.
2. Ayers JF. The use of alternative therapies in the support of breastfeeding. J Hum Lact. 2000;16:52-6. PMID:11138225
3. Low Dog T. The use of botanicals during pregnancy and lactation. Altern Ther Health Med. 2009;15:54-8. PMID:19161049
4. Dennehy C, Tsourounis C, Bui L, King TL. The use of herbs by California midwives. J Obstet Gynecol Neonatal Nurs. 2010;39:684-93. PMID:21044150
5. Alachkar A, Jaddouh A, Elsheikh MS et al. Traditional medicine in Syria: folk medicine in Aleppo governorate. Nat Prod Commun. 2011;6:79-84. PMID:21366051
6. Winterfeld U, Meyer Y, Panchaud A, Einarson A. Management of deficient lactation in Switzerland and Canada: A survey of midwives' current practices. Breastfeed Med. 2012;7:317-8. PMID:22224508
7. The Academy of Breastfeeding Medicine Protocol Committee. ABM clinical protocol #9: use of galactogogues in initiating or augmenting the rate of maternal milk secretion (First revision January 2011). Breastfeed Med. 2011;6:41-9. PMID:21332371
8. Dreyfus-See G. Le passage dans le lait des aliments ou medicaments absorbes par les nourrices. Rev Med. 1934;51:198-213.
9. Hausner H, Bredie WL, Molgaard C, Petersen MA, Moller P. Differential transfer of dietary flavour compounds into human breast milk. Physiol Behav. 2008;95:118-24. PMID:18571209
10. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal teamixturein two newborns. Acta Paediatr. 1994;83:683. Letter. PMID:7919774
11. Nikolov P, Avramov NR. [Investigations on the effect of Foeniculum vulgare, Carum carvi, Anisum vulgare, Crataegus oxyacanthus, and Galga officinalis on lactation]. Izv Meditsinskite Inst Bulg Akad Naukite Sofia Otd Biol Meditsinski Nauki. 1951;1:169-82. PMID:14888359
12. Nobrega S, Francenely N. [Aniseed and its galactogenous effect. An experimental study]. Rev Bras Enf. 1983;36:163-77. PMID:6566378

Substance Identification:

Substance Name:


Scientific Name:

Pimpinella anisum

Drug Class:

  • Complementary Therapies

  • Galactogogues

  • Phytotherapy

  • Plants, Medicinal

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

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