Phentermine Withdrawal BySally Cohen Updated onJune 28, 2023 Phentermine should only be taken for twelve weeks at a time.This recommendation is related to the active ingredient’s strong potential for addiction and abuse, as well as a lack of research on the long-term effects of this medication ( 1 ). Plus, limiting use to “a few weeks” minimizes patients’ risk of dependency, tolerance, and withdrawal.Unfortunately, some people still experience withdrawal symptoms when they stop taking phentermine – even after a relatively short course of treatment.Table of ContentsStopping PhenterminePhentermine Withdrawal SymptomsHow Long Does Phentermine Withdrawal Last?Life After PhentermineStopping Phentermine Daily activity should be part of your plan for how to stop taking phenterminePlanning how to stop phentermine is important to help minimize phentermine withdrawal symptoms.Phentermine is designed to be used alongside lifestyle modifications that promote weight loss ( 2 ). As you reach the end of your 12-week treatment period, focus on reinforcing healthy eating, exercise, and self-care habits.A strong support system, whether in-person or online, can help you stay committed to your new, healthier lifestyle.For some patients, it’s also beneficial to taper phentermine dosage in the final weeks of treatment. A taper allows the body to gradually adjust to a lower level of stimulant, which helps reduce the risk of phentermine withdrawal.If possible, do not stop phentermine “cold turkey,” or very suddenly ( 2 ).Read more here: Stopping PhenterminePhentermine Withdrawal Symptoms One of the most common phentermine withdrawal symptoms is fatiguePhentermine withdrawal symptoms are similar to those associated with other stimulants.Common reactions include fatigue, depression/mood changes, insomnia, gastrointestinal upset and trembling ( 3 , 4 ). Severity varies significantly from person-to-person.Call your doctor or seek immediate medical attention if withdrawal symptoms are severe, worsening or interfering with daily life.Take extra care to monitor for signs of depression and low mood, which are the typically the most dangerous side effects of stimulant withdrawal, even months after the last dose ( 5 ).Read more here: Phentermine Withdrawal SymptomsHow Long Does Phentermine Withdrawal Last? Duration of phentermine withdrawal varies from person to personDuration of phentermine withdrawal varies from person to person. However, most people withdrawing from stimulants experience the most acute symptoms during the first four days, after which point they begin to feel better.Lingering symptoms of stimulant withdrawal, such as low mood or fatigue, can last for weeks or months after stopping phentermine ( 5 ).Read more here: Phentermine Withdrawal TimeLife After Phentermine Adopting healthy habits during treatment may help you ease into life after phentermineIt’s critical that patients transition off phentermine with a plan for continued healthy living.In fact, without a strong weight maintenance plan in-place, almost 80% of people who achieve major weight loss gain the pounds back within two years ( 6 ).However, research shows that certain behaviors are highly-correlated with successful weight maintenance ( 7 ). These healthy habits include:LEARN ABOUT PHENTERMINEGet your FREE Phentermine Guide!Learn more about popular brands, dosage, side effects, results, and weight loss alternatives.Get my eBook Eating breakfastWeighing regularlyCooking at homeStaying activeRead more here: Life After PhentermineReferences Weintraub M, Hasday JD, Mushlin AI, Lockwood DH. (1984). A double-blind clinical trial in weight control. Use of fenfluramine and phentermine alone and in combination. Archives of Internal Medicine, 144(6):1143-1148.American College of Cardiology. (2011, November 21). Phentermine.Allina Health. (2013, June 12). Appetite suppressant, sympathomimetic.Drugs.com. (2022, November 10). Phentermine Hydrochloride Drug Information, Professional.Center for Substance Abuse Treatment. (1999). Chapter 5 – Medical Aspects of Stimulant Use Disorders. In Treatment Improvement Protocol (TIP) (Ser. 33).McGuire, MT, Wing, RR, & Hill, JO. (1999). The prevalence of weight loss maintenance among American adults. International Journal of Obesity and Related Metabolic Disorders, 23(12), 1314-1319.Wing, R. R., & Phelan, S. (2005). Long-term weight loss maintenance. The American Journal of Clinical Nutrition, 82(1), 222S-225S.