From Dr. Tom Hale's website, he does all the research on drugs and mother's milk:

International Registry for Lactation Research

At this time I am enrolling patients in the following drug studies...and I need patients desperately. If you are taking these medications and breastfeeding, please register immediately and I will contact you.

Ritalin (methylphenidate)
Interferon Beta

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Research in human lactation is sometimes rather limited by a shortage of eligible volunteers. This registry has been developed to provide the scientific community with a registry of potential volunteers for studying human lactation under special circumstances. These circumstances include certain medical conditions, problems with lactation, and use of specific drugs during breastfeeding. Women who are currently breastfeeding, and/or women planning to breastfeed after delivery, are included in this registry. For those of you outside the USA, you are most welcome to register as well.


Mothers and Expectant Mothers:

If you have one of the cited medical conditions or syndromes below, or if you are currently taking one of the medications listed, you may be able to participate in a research project that will benefit other women like yourself in the future. We are also taking information from mothers who are not taking medications to use as ‘normals’.

If you sign up with this registry, your information will be held strictly confidential with one exception: It will be shared with scientists certified by Dr. Tom Hale, Dr. Judy Hopkinson, and other board members, as legitimate researchers with a valid need for this data. On occasion, you might receive a call or email from one of these researchers with a request for milk samples, or perhaps some other piece of data. The decision to supply samples or to provide additional information is totally up to you. We do not intend to store or collect milk, that is up to the investigator themselves.

If you wish to add your name to this National Registry for Breastfeeding Research, please review the list of needed areas and fill out the following forms by clicking on the button below.

At this time I am enrolling patients in the following drug studies...and I need patients desperately. If you are taking these medications and breastfeeding, please register immediately and I will contact you.

Ritalin (methylphenidate)
Interferon Beta

http://neonatal.ttuhsc.edu/lact/html..._registry.html