Dear Colleague:
As a follow up to my January 17, 1990, letter to you on L-tryptophan, I would like to bring you up to date with further developments and to provide a clarification of some of the legal and regulatory background on L-tryptophan.
Current Number of Cases
As of January 25, 1990, reports of 1,143 cases of eosinophilia-myalgia syndrome (EMS) possibly associated to L-tryptophan supplements have been made to the federal Centers for Disease Control (CDC) in Atlanta. These include nine deaths, one of which has been confirmed as being clearly associated with the taking of L-tryptophan.
Treatment of EMS
As editorial by the CDC appeared in the Annals of Internal Medicine, "Interim Guidance on the Eosinophilia-Myalgia Syndrome," Volume 12, Number 2, January 15, 1990. That editorial offers information on therapy for EMS.
Recall
On November 17, 1989, FDA requested an urgent recall of L-tryptophan products, and 331 manufacturers, repackers, and distributors have complied. However, while saying that they "may recall" their products, NutriCology and Allergy Research representatives have refused to furnish FDA with any proof that any such recall has been initiated. In addition, FDA visits to several stores have shown no evidence of a recall. For that reason, consumers have been warned against using the following products:
Legal and Regulatory Status
It is necessary to clarify certain information that inadvertently appeared in the January 17, 1990 letter. On page two of that letter, it was suggested that over-the-counter L-tryptophan dietary supplements that provide for the intake of less than 100 mg daily were lawfully marketed. This is incorrect. While the FDA has not asked for a recall of those products, L-tryptophan is not approved for use in dietary supplements. There are only two types of approved uses of
L-tryptophan as a nutrient: (1) as an additive in food containing naturally occurring primarily-intact protein that is considered a significant dietary protein source; and (2) as an additive in special dietary foods that are intended for use solely under medical supervision to meet nutritional requirements in specific medical conditions. 21 CFR 172.320. Neither approved use provides for the marketing of L-tryptophan as a component of an over-the-counter dietary supplement.
On page three of the January 17, 1990 letter, it was suggested that L-tryptophan is generally recognized as safe and effective for use as a nutritional replacement. This is incorrect. The FDA does not consider L-tryptophan as generally recognized as safe and effective for any use.
L-tryptophan is an approved food additive when used, as described above, for nutritional purposes.
FDA Contacts
Dr. Douglas Archer (202-245-1057) or Dr. Richard Calvert (202-245-7862) (see updated contact information below) of FDA's Center for Food Safety and Applied Nutrition may be contacted for questions concerning L-tryptophan for non-drug use.
Mr. Patrick Savino (301-295-8012) of FDA's Center for Drug Evaluation and Research may be contacted for questions regarding drug use of L-tryptophan.
We will let you know as further information on aspects of the EMS and L-tryptophan becomes available.
Sincerely yours,
/S/
Stuart L. Nightingale, M.D.
Associate Commissioner for
Health Affairs
Updated contact information: Dr. Nancy Slifman (202 205-5056)
This document was issued on February 2, 1990.
For more recent information on Dietary Supplements
See http://www.cfsan.fda.gov/~dms/supplmnt.html
Hypertext updated by ear/dms/kwg 2000-NOV-14