Drug compounds have included stable heavy isotopes of carbon, hydrogen, and other elements, mostly as quantitative tracers while the drugs were being developed. Because deuteration may have an effect on a drug's pharmacokinetics and metabolic properties, it is a cause for concern [1].

Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation
Ursodeoxycholic acid (UCCA) is naturally present in breast milk. Due to the low levels of UCCA in breast milk after exogenous administration, and the minimal intake by the infant, no adverse effects are expected on breastfed infants. Usodeoxycholic acid has been used directly in newborns, safely and effectively treating neonatal jaundice. No special precautions are required.
◉ Effects on Breastfed Infants
One breastfed infant (feeding extent not specified) developed normally in the first 6 months after birth, with the mother taking 750 to 1000 mg of UCCA daily.
Seven women took 14 mg/kg of UCCA daily near delivery and postpartum. They reported no adverse reactions in breastfed infants in the early postpartum period.
A mother with primary biliary cirrhosis reportedly took 250 mg of ursodeoxycholic acid three times daily and breastfed her infant normally, but the extent and duration of breastfeeding were not specified.
A woman with primary biliary cirrhosis developed severe itching and elevated serum bile acids three weeks postpartum. She started taking ursodeoxycholic acid at a dose of 500 mg (7.5 mg/kg) daily, increasing to 1500 mg (25 mg/kg) daily over the next eight weeks. Her breastfed infant (feeding extent not specified) showed normal psychomotor development, and no significant side effects were observed.
A retrospective analysis of medical records of pregnant women diagnosed with primary biliary cirrhosis at a hospital in Ankara, Turkey, found that eight patients took ursodeoxycholic acid postpartum at a dose of 13-15 mg/kg daily. "Most" of these patients breastfed their infants (feeding extent not specified). No side effects were reported in the infants.
A woman breastfed her 8-day-old premature infant 10 times a day, each time for about 15 minutes. The infant was delivered by cesarean section at 34 weeks of gestation, weighing 3600 grams. She was diagnosed with cholestasis, type 1 diabetes, and hypothyroidism. She received ursodeoxycholic acid 500 mg/day, insulin Lantus and aspart, and levothyroxine. She also took cefuroxime, flurbiprofen, and a combination of acetaminophen, disopyrfenone, and caffeine. The mother took ursodeoxycholic acid for 12 days, cefuroxime and the above-mentioned combination analgesics for 10 days, and flurbiprofen for 15 days. No adverse reactions were observed during ursodeoxycholic acid treatment.
Twenty lactating women with cholestasis received ursodeoxycholic acid at a daily dose of 500 to 1500 mg or 13 to 15 mg/kg, depending on their condition. Ursodeoxycholic acid was discontinued 3 days postpartum. Based on standard clinical examinations of newborns in the early postnatal period, no significant side effects were observed in any newborns; no postnatal developmental deterioration was also observed during a one-year follow-up period following routine pediatric examinations.
◉ Effects on breastfeeding and lactation
As of the revision date, no relevant published information was found.

[1]. Impact of Deuterium Substitution on the Pharmacokinetics of Pharmaceuticals. Ann Pharmacother. 2019;53(2):211-216.

[2]. Influence of ursodeoxycholic acid on the mortality and malignancy associated with primary biliary cirrhosis: a population-based cohort study. Hepatology. 2007 Oct;46(4):1131-7.

[3]. Use of ursodeoxycholic acid in liver diseases. J Gastroenterol Hepatol. 2001 Jan;16(1):3-14.

[4]. Specific Bile Acids Inhibit Hepatic Fatty Acid Uptake in Mice. Hepatology. 2012 Oct;56(4):1300-10.

[5]. FXR inhibition may protect from SARS-CoV-2 infection by reducing ACE2. Nature. 2022 Dec 5.

Reports indicate that 3,7-dihydroxycholan-24-acid has been found in goose (Anser anser), and relevant data are available for reference.

C24H36D4O4

396.60

396.318

347841-46-7

5645

White to off-white solid powder

4.477

3

4

4

28

605

0

RUDATBOHQWOJDD-UHFFFAOYSA-N

InChI=1S/C24H40O4/c1-14(4-7-21(27)28)17-5-6-18-22-19(9-11-24(17,18)3)23(2)10-8-16(25)12-15(23)13-20(22)26/h14-20,22,25-26H,4-13H2,1-3H3,(H,27,28)

4-(3,7-dihydroxy-10,13-dimethyl-2,3,4,5,6,7,8,9,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl)pentanoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)