Purpose: Evaluate weight maintenance in subjects who lost weight while taking phentermine (PTM). Methods: This study was conducted by utilizing a validated survey to collect self-reported data about weight changes post-PTM use. The survey was sent to 19,986 email addresses of current and former patients of a PTM-based outpatient clinic, located in Chicago, IL; 546 participants completed the survey. Results were analyzed using a variety of techniques. Results: At the time of the survey, 42% of responders maintained all the weight lost while on PTM, and 25.2% had maintained a weight loss of at least 10% of their body weight. The average weight lost and maintained at the time of the survey was 3.75% ± 13.8% of body weight or 8.74 lbs ± 27.45 lbs. Nineteen responders had no net weight change. Fifty-nine responders reported a net weight gain, ranging from 2 to 70 lbs with a mean net weight gain of 16.07 lbs ± 13.87 lbs. The duration of time since discontinuing PTM use had a significant correlation with weight maintenance: r = 0.340, p value = .000. There was no significant correlation between duration of time using PTM and weight maintenance. No correlations were identified between education, income, or ethnicity and weight maintenance. A correlation was identified between weight maintenance and current exercise level: r = 0.218, p value = .000. Conclusions: Although more research is needed, with the results of this study, the investigators suggest that post-PTM use, weight regain is not significantly higher than weight regain through other weight loss programs. In order to achieve long-term weight loss maintenance, it may behoove patients to receive professional guidance about behavior modifications to maintain weight lost, particularly related to exercise and dietary changes. The investigators of this study suggest greater emphasis on behavior modification in patients taking PTM is indicated.

Author Bio(s)

Cassandra Steadman Towns, RDN, LDN, CD is the Whole Health Program Manager at the Tomah Veteran Affairs Medical Center. She earned her Bachelor's in Dietetics from the University of Wisconsin Stevens Point and her Master's in Nutrition and Dietetics from Central Michigan University.

John V. Logomarsino,PhD, RD, LD/N is Professor Emeritus in Nutrition and Dietetics at Central Michigan University. He has 45 years of experience in teaching and research on subjects relating to nutrition science, nutrition education, and health.

Roschelle Heuberger, PhD, RD, is a Professor of Nutrition at Central Michigan University. She completed her doctoral studies and post-doctoral fellowship at the University of Wisconsin- Madison in Nutritional Sciences and Nutritional Epidemiology. She currently sits on the Board for the Medical Nutrition Council of the American Society of Nutrition.

Arturo Olivera Jr, MD, is the owner of Arturo Olivera Jr LTD, the Medical Director of Olivera Weight Management S.C., the Chief Section Gastroenterology at Advocate Illinois Masonic Medical Center, and the owner of Ghazanfari & Olivera Gastroenterology LTD. He is a Clinical Assistant Professor at Loyola University Medical Center.



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