By Author


of the The Nutritional Therapy Institute Clinic

(formerly The Recovery Systems Clinic)

Restoring the Natural Opioid System with D-Phenylalanine (DPA):
A Novel Therapeutic Approach

By Julia Ross MA, MFT

Published in Practical Pain Management, Nov/Dec 2009, Vol. 9, Issue 9, pp 29-31

TABLE 1.Beta-Endorphin and ACTH 20-chain Amino Acid Compositions





The body produces its own powerful pain-modulating neurotransmitters. Chronic pain and other chronic stressors, combined with a diet low in protein, can create deficiencies in the three most critical of these pain-modulators: serotonin, gamma-amino-butyric acid (GABA), and endorphin. (1-3)In earlier articles in Practical Pain Management, we discussed the use of diet and amino acid supplementation in promoting optimal levels of serotonin and GABA. This article targets the use of diet and amino acids in the optimization of the endogenous opiates, the endorphins-our most potent natural analgesics. Endorphin is a term used to identify a group of naturally-occurring compounds that can powerfully reduce pain.(1) Primary among them are the beta-endorphins and the enkephalins. These endogenous opioids, molecule-for-molecule, are thousands of times stronger than morphine.(2,3) B-Endorphin is composed of 20 amino acids (see Table 1). Amino acids are the constituents of protein-containing foods. There are a total of 22 amino acids found in these foods in varying amounts. If adequate protein is consumed, endorphin levels may remain high enough to effectively modulate pain. Chronic pain sufferers, however, typically become significantly deficient in their endorphin-producing capacity.(1-3)

The 21st century U.S. diet is often inadequate in protein content. It is also low in the anti-inflammatory vitamin and mineral co-factors which are typically found in fresh vegetables and fruits. Pain and the medications needed for relief can both reduce appetite and further reduce the intake of nutrients vital to the production of endorphins. Since opiate medications depend on endorphin activity to support their effectiveness, supplying the amino acid building blocks for the production of additional endorphins can be critically beneficial.


To raise and sustain endorphin levels, daily protein consumption should be at least 30 grams, three times per day. Pain patients rarely meet these minimal protein requirements. In particular, they skip breakfast and often eat primarily sugars and starches during the remainder of the day. Aggressive counseling may be required to increase a pain patient's intake of foods that contain significant amounts of protein. Higher quantity is needed post-surgery or post-infection. Providing an amino acid supplement that contains most or all of the 22 amino acids-including the nine essential amino acids-can be very helpful. Finally, the therapeutic use of particular amino acids in supplement form can often provide surprisingly quick and dramatic improvements in pain relief.Use of D-Phenylalanine to Raise Endorphins

The amino acid d-phenylalanine (DPA) slows the action of the enzymes-particularly carboxypeptidase A or endorphinase and enkephalinase-that degrade the endorphins. (4-7)The enzymatic degradation of endorphins and enkephalins is a constant, somewhat indiscriminate, process. Slowing down this endorphin-reducing mechanism can diminish pain within twenty-four hours. In our clinic, we have seen pain relief occur within ten minutes after the ingestion of as little as 500mg of DPA. Our usual dose in chronic pain patients is 500-2000mg of d-phenylalanine, two to four times a day.

D-phenylalanine's endorphin-protective properties were researched and confirmed in the 1980s in trials conducted at the Chicago Medical School by pharmacology professor Seymour Ehrenpreis, PhD.(4,5) Dr. Ehrenpreis was motivated by the urgent need to assist the medical staff in reducing the doses of opiate medications used in their hospital. He, and subsequently several other researchers, have confirmed the usefulness of this benign amino acid in acute as well as chronic pain management.(6,7) Still other researchers have combined DPA with acupuncture with additional benefit.

Relationship of D- And L-Phenylalanine

DPA, a non-nutritive amino acid is available alone or bound to I-phenylalanine (LPA) as DLPA. LPA is an essential amino acid used by the body to create a number of vital compounds, including I-dopa, dopamine, norepinephrine, adrenalin, and thyroid hormone. DPA has twice the endorphinase inhibitory effect of DLPA, while DLPA is more energizing and more readily available in health food stores, pharmacies, and online. For anxious or agitated patients, DLPA can sometimes be experienced as overly stimulating, while more mood-stable patients find it to be both pain-relieving and energy-enhancing. Our recommended DLPA dose is: 1000-2000mg, three times a day. I recommend that patients with malignant melanoma, extremely high blood pressure, Grave's disease, constant migraine, or phenylketonuria avoid DLPA.

Clinical Experience

Our outpatient clinic has used both DPA and DLPA successfully since 1990, as have other practitioners. Paul Anderson, MD, a pain specialist and CEO of Natural Pain Relief Center, and former president of the Canadian Institute of Biomechanics, has been experimenting with alternative pain management methods for many years. He has found DPA to be very effective when combined with a high protein/high vegetable diet. He's also found that low levels of microelectrie current can initially amplify the effects of the nutrients. His results: "93.1% of my patients using a combination of electromagnetic current, proper diet, nutritional supplements with amino acids and meditation/relaxation experienced significant long-Iasting chronic pain relief without any pain medication. Most patients took a minimum of 1000mg of DPA four times a day initially and didn't require it for pain control after 14 days."


Laboratory and clinical reports indicate that DPA may reduce pain by inhibiting the enzymatic degradation of endorphin and enkephalin. This is an inexpensive therapy that can be used for acute or chronic pain and can be used as an ancillary treatment to opioids and other measures.

Julia Ross, MA, MFT is the founder and Executive Director of The The Nutritional Therapy Institute Clinic. She is internationally recognized as a pioneer in the field of nutritional psychology. Her work has identified the key physiological causes of depression and anxiety, overeating, and addiction. She and the clinic's team of nutritionists, psychotherapists, and physicians have developed innovative and effective solutions to these problems.

Julia began directing treatment programs for adults and adolescents in 1980 and has founded and directed seven programs in the San Francisco Bay Area since then. Her earlv work alerted her to the limitations of psychotherapy and drug therapy and led her to investigate research on nutritional therapy and to incorporate it into a new, holistic model of treatment.

Julia is the author of The Diet Cure and The Mood Cure, both based on The The Nutritional Therapy Institute Clinic's successful programs. Her books have sold well in the US, UK, and Australia, and are being translated into Japanese and German. Julia has frequently been featured on radio, television and in print. She has presented at hundreds of professional conferences internationally and trains health professionals throughout the US in the nutritional therapy methods developed at the Clinic. Julia Russ may be contacted at her The Nutritional Therapy Institute Clinic by phone 415-383-3611 or her website,


1. Almay BG, Johansson F: Von Knorring L, Terenius L, and Wahlstrom A. Endorphins in chronic pain. Pain, Aug 1978. 5(2): 153-162

2. Von Knorring L, Almay BGL, Johansson F, and Terenius L. Endorphins in CSF of chronic pain patients, in relation to augmenting-reducing response in visual averaged evoked response. Neuropsychobiology. 1979.5: 322-326

3. Almay BGL, Johansson G, Von Knorring L, Sedvall G, and Terenius L. Relationships between CSF levels of endorphins and monoamine metabolites in chronic pain patients. Pschopharmacol. 1980 67:139-142

4. Ehrenpreis, S., Balagot RC, Myles S, Advocate C, and Cornaty JE. Further Studies on the Analgesic Activity of D-Phenylalanine in Mice and Humans. Proceedings of the International Narcotic Research Club Convention. E. L. Way, ed. 1979, pp 379-382

5. Balagot RC, Ehrenpreis S, Kubota K, et al. Analgesia in mice and humans by D-phenylalanine: Relation to inhibition of enkephalin degradation and enkephalin levels. Adv Pain Res Ther 1983. 5:289-293

6. Budd K. Use of D-phenylalanine, an enkephalinase inhibitor, in the treatment of intractable pain Adv Pain Res Ther, 1983.5: 305-308

7. Walsh NE, Ramamurthy S, Schoenfeld LS, et al Analgesic effectiveness of D-phenylalanlne In chronic pain patients. Arch Phys Med Rehab. 1986.67:436-439.