Methenamine use while Breastfeeding

Drugs containing Methenamine: Uribel, Hiprex, Urex, Urogesic Blue, Cystex, Mandelamine, Urimax, Urelle, Hyophen, Methylphen, Show all 58 »Phosphasal, Uretron, Uro-MP, Uretron DS, Uramit MB, Ustell, Urin D/S, Urised, Uro-458, Urimar-T, Uroqid-Acid No2, Prosed EC, Indiomin MB, Uro-L, Uritin, Utira-C, Uro Blue, Urolet MB, Utac, Visqid AA, Uro-Phosphate, Uta, UR N-C, UroAv-B, UroAv-81, Hyolev MB, Azuphen MB, Phosenamine, Dolsed, Cystemms-V, Urapine, MSP-Blu, Atrosept, Trac Tabs 2x, Prosed DS, Urophen MB, Urisedamine, MHP-A, Usept, Uritact-EC, Darcalma, Darpaz, UTICAP, Utrona, Uritact DS, Utira, UriSym, Utrona-C

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.

Drug Levels

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.[1]

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.[1]

Effects on Lactation and Breastmilk

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

Alternate Drugs to Consider

Methenamine Hippurate, Methenamine Mandelate

References

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

Methenamine Identification

Substance Name

Methenamine

CAS Registry Number

100-97-0

Drug Class

Antiinfective Agents, Urinary

Antibacterial Agents

Administrative Information

LactMed Record Number

175

Last Revision Date

20130907

Disclaimer

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.

Disclaimer: This information is not intended as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. Use of this website signifies your agreement to the Terms of Use and Online Privacy Policy.