Methenamine use while Breastfeeding
Drugs containing Methenamine: Uribel, Hiprex, Phosphasal, Urogesic Blue, Urimax, Cystex, Ustell, Uta, Mandelamine, Hyophen, Show all 60 »Urex, Urised, Urelle, UTICAP, Uretron DS, Darpaz, Vilamit MB, Uretron, Uro-MP, Phosenamine, Uro Blue, Prosed EC, Azuphen MB, Utira-C, UriSym, UR N-C, Urimar-T, Vilevev MB, Uro-458, Cystemms-V, Urisedamine, Hyolev MB, Indiomin MB, Urolet MB, Urophen MB, Methylphen, Uroqid-Acid No2, Utac, Visqid AA, Uramit MB, Urin D/S, UroAv-81, Darcalma, MSP-Blu, MHP-A, Usept, Uritact DS, Utira, Utrona, Uritact-EC, Utrona-C, UroAv-B, Prosed DS, Dolsed, Atrosept, Uritin, Trac Tabs 2x, Uro-L, Urapine, Uro-Phosphate
Methenamine Levels and Effects while Breastfeeding
Summary of Use during Lactation
Both the hippurate and mandelate salts of methenamine pass into milk in small quantities and appear acceptable to use, even while nursing a newborn.
Maternal Levels. Six mothers nursing newborn infants were given methenamine hippurate 1 g orally. Five hours after the dose, a mean methenamine concentration of 7 mg/L was found in milk. In two other women, milk concentrations averaged 9.1 mg/L 2 to 3 hours after a 1 g dose of methenamine hippurate orally and 4.3 mg/L 6 to 7 hours after the dose. Based on the amount of milk ingested, the authors calculated the dose the infants received to be 0.05 to 0.1 mg/kg which is about 1% of the adult dose.
Infant Levels. Relevant published information was not found as of the revision date.
Effects in Breastfed Infants
Four newborn infants were allowed to breastfeed in one study after a maternal dose of 1 gram of methenamine hippurate. No adverse effects were reported.
Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.
Alternate Drugs to Consider
1. Allgen LG, Holmberg G, Persson B et al. Biological fate of methenamine in man. Acta Obstet Gynecol Scand. 1979;58:287-93. PMID: 484222
CAS Registry Number
Antiinfective Agents, Urinary
LactMed Record Number
Last Revision Date
Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
More about methenamine
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- Support Group
- Pricing & Coupons
- En Español
- 27 Reviews – Add your own review/rating
- Drug class: urinary anti-infectives