Acute and Immediate Impact of Hythiam's PROMETA(R) Protocols on Cravings and Cognition to Be Evaluated in Additional Double-Blind Placebo-Controlled Studies.

Renowned Alcoholism Researcher Dr. Joseph R. Volpicelli to Supervise Study of PROMETA([R]) on Alcohol Dependent Subjects; Dr. Harold C. Urschel III to Investigate Effects among Methamphetamine Dependent

LOS ANGELES -- Hythiam, Inc. (NASDAQ:HYTM), a healthcare services management company that licenses the PROMETA([R]) treatment protocols designed to treat alcohol, methamphetamine and cocaine dependence, announced today that leading researchers will conduct additional studies to assess PROMETA's acute effects on reducing cravings and improving neurocognitive functioning. The Institute of Addiction Medicine's Dr. Jenny Starosta will conduct a double-blind placebo-controlled study designed and supervised by renowned alcoholism researcher, Dr. Joseph R. Volpicelli of the University of Pennsylvania, of the PROMETA protocol for the treatment of alcohol dependence. The second double-blind placebo-controlled study will be conducted by Dr. Harold C. Urschel III of Research Across America on the PROMETA protocol for methamphetamine dependence. This study is a follow up to Dr. Urschel's previously conducted single-arm, open-label study of PROMETA with 50 methamphetamine dependent subjects.

In addition to these two new studies, Hythiam is pending anticipated outcomes from three current clinical evaluations of the PROMETA protocols. Dr. Jeffrey Wilkins of Cedars-Sinai Hospital is conducting an open-label investigation of PROMETA for the treatment of alcohol dependence which he will follow up with a double-blind placebo-controlled study of PROMETA for alcohol dependence. Additionally, UCLA's Dr. Walter Ling and the Medical University of South Carolina's Dr. Raymond Anton are conducting randomized, double-blind placebo-controlled studies of the PROMETA protocol for methamphetamine dependence and alcohol dependence, respectively.

"The two effects that have been observed repeatedly in evaluations of the PROMETA protocols have been reduced cravings and improved cognition," said Terren Peizer, Hythiam's Chairman and CEO. Third party payors have expressed great interest in these phenomena and these short-term studies will serve to provide them with definitive data on these two endpoints that are so critical to recovery. These near-term studies should complement the longer-term abstinence outcomes also expected in 2007 from investigations being conducted by Drs. Ling, Wilkins, and Anton.

Peizer continued, "Drs. Volpicelli, Starosta, and Urschel will focus on PROMETA's effects during the important phase of early abstinence, investigating immediate therapeutic benefit which could have an effect on the long-term prognosis of addictive disease. To date, there have been five separate sets of data from completely independent and unrelated entities that have provided compelling evidence supporting PROMETA's impact on sustained recovery. Retrospective analyses from PROMETA licensees Little Company of Mary and LifeWorks, pilot results from Gary, Indiana and the Pierce County Alliance, and data from Dr. Harold Urschel's open label study have all demonstrated PROMETA's dramatic effect on recovery in geographically diverse populations comprised of patients dependent on different substances including cocaine, crack cocaine, alcohol, methamphetamine and poly-addictions of those substances."

"It is well known that alcoholic dependent individuals have cognitive deficits that interfere with memory, advance planning, and controlling impulses," said Dr. Volpicelli. "This combined with intense cravings that follow an individual's abstinence from alcohol are major contributors to relapse. Treatment that can normalize these cognitive deficits and diminish cravings can facilitate recovery by improving treatment adherence, reducing urges to drink, resulting in overall improvement of abstinence outcomes. We are interested to see if PROMETA will immediately effect a patient's executive abilities and if it allows them to discern between positive and detrimental choices as they enter the critical first few weeks of recovery, during which time they are most vulnerable to relapse."

Dr. Volpicelli is an associate professor of psychiatry at the University of Pennsylvania, noted for pioneering the integration of medication with psychosocial support to treat substance dependence. His research on the use of naltrexone led to the first new medication to be approved by the FDA for alcohol treatment in nearly 50 years. Dr. Volpicelli developed a new model for psychosocial treatment based on techniques to enhance motivation and medication compliance called the BRENDA model.

Dr. Volpicelli's study will measure outcomes on 60 alcohol dependent subjects with a battery of standardized neurocognitive tests following treatment with the PROMETA protocol for alcohol dependence. Subjects will be randomly assigned to receive the PROMETA protocol or placebo. Tests will measure executive functioning, verbal memory, general intelligence, and attention. Additional aims of the study are to determine the efficacy and safety of the PROMETA protocol by measuring alcohol craving, subject retention, percent of heavy drinking days, time to first heavy drinking day, and blood chemistries including liver enzymes and reports of side effects. The final aim of the study is to investigate in a preliminary way the characteristics of individuals who may be most likely to benefit from the PROMETA protocol for alcohol dependence.

Dr. Urschel's previous open-label study of methamphetamine dependent subjects found that more than 80% of study participants experienced a significant clinical benefit with no adverse events after treatment with the PROMETA protocol for methamphetamine. Clinical benefit was measured by decrease in cravings, increase in methamphetamine abstinent days, and treatment retention. In his current double-blind study of the PROMETA protocol for the treatment of methamphetamine dependence, 84 subjects will be followed for 30 days, half of whom will receive the PROMETA protocol with the other half receiving placebo.

"My ongoing interest in the PROMETA protocols is due to the impressive results we observed in our open label study of the PROMETA protocol with methamphetamine dependent subjects," said Dr. Urschel. "With this new randomized double-blind placebo controlled study, we hope to shed further light on PROMETA's potential to reduce cravings and restore neurocognitive function in persons addicted to methamphetamine during the important days and weeks following cessation of meth use."

The neurocognitive domains to be assessed among methamphetamine dependent include short-term memory, concentration, executive function, and verbal learning. Standardized tests will be administered at baseline and days 4, 6, 13, 20, and 30 and will be used to compare PROMETA versus placebo improving the neurocognitive functioning of methamphetamine-dependent subjects during early abstinence. The study also aims to determine whether subjects treated with PROMETA have reductions in cravings and more drug-free days than subjects receiving placebo. PROMETA's efficacy on subjects' perceived disability and quality of life will be investigated as well as its effect on altering drug-related sexual practices.

About PROMETA([R])

Hythiam's PROMETA([R]) treatment protocols are designed for use by healthcare providers seeking to treat individuals diagnosed with dependencies to alcohol, cocaine or methamphetamine, as well as combinations of these drugs. The PROMETA treatment protocols are an integrated treatment comprised of nutritional supplements, FDA-approved oral and IV medications used off-label and separately administered in a unique dosing algorithm, as well as psychosocial or other recovery-oriented therapy chosen by the patient and his or her treatment provider. As a result, PROMETA represents an innovative approach to managing alcohol, cocaine, or methamphetamine dependence that is designed to address physiological, nutritional, and psychosocial aspects of the disease, and is thereby intended to offer patients an opportunity to achieve sustained recovery. To learn more, please visit www.prometainfo.com.

About Hythiam, Inc.

Hythiam([R]) is a healthcare services management company focused on delivering solutions for those suffering from alcoholism and other substance dependencies. Hythiam researches, develops, licenses and commercializes innovative physiological, nutritional, and behavioral treatment protocols that seek to address substance dependence. Additionally, Hythiam provides proprietary administrative services to assist physicians and facilities with staff education, training, marketing and outreach support, and outcomes tracking for data analysis. For further information, please click on www.hythiam.com.

Forward-Looking Statements

Except for statements of historical fact, the matters discussed in this press release are forward looking and made pursuant to the Safe Harbor provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements reflect numerous assumptions and involve a variety of risks and uncertainties, many of which are beyond the company's control that may cause actual results to differ materially from stated expectations. These risk factors include, among others, limited operating history and lack of statistically significant formal research studies, the risk that treatment protocols might not be effective, difficulty in developing, exploiting and protecting proprietary technologies, intense competition and substantial regulation in the healthcare industry; and additional risks factors as discussed in the reports filed by the company with the Securities and Exchange Commission, which are available on its website at http://www.sec.gov.