Recurrent Psychosis after Phentermine Administration in a Young Female: A Case Report

Phentermine is a sympathomimetic amine, like amphetamine, which is one of the most often prescribed drugs for weight loss. Although exact mechanism of phentermine causing psychosis is still not clear, numerous reports already showed that phentermine can induce psychosis. Psychotic symptoms are generally resolved once the medications are stopped. In contrast, we present a case of a 25-years-old Asian female patient who developed psychotic symptoms repeatedly after phentermine administrations. This case suggests that phentermine can cause psychotic episodes repeatedly, resulting in chronic occupational and social impairment. Therefore, a precautious measure such as government regulations for physicians prescribing and an education for patients taking phentermine are urgently needed.

Psychotic Disorder Induced by Appetite Suppressants, Phentermine or Phendimetrazine: A Case Series Study

OBJECTIVES: A retrospective case series study was conducted to investigate the clinical characteristics of psychotic disorders induced by appetite suppressants, phentermine and phendimetrazine. METHODS: A retrospective electronic medical record review identified 5 admitted patients who had psychotic symptoms after taking phentermine or phendimetrazine. Clinical information was reviewed and summarized in each case. RESULTS: Hallucinations were reported in all cases, including auditory, visual, olfactory and somatic hallucinations. After discontinuation of phentermine or phendimetrazine, the symptoms rapidly improved with low dose of antipsychotics. Patients tended to have less prominent negative symptoms and higher insight into illness, and often showed depressive mood. These clinical characteristics were similar to psychosis induced by amphetamines. Two patients developed stimulant use disorder while using phentermine. CONCLUSIONS: These findings call for awareness of the risks associated with use of appetite suppressants. Prescription of phentermine or phendimetrazine should be accompanied by close monitoring of mental status, and suspicion for substance/medication-induced psychotic disorder.

Intracerebral Hemorrhage related to Phentermine as an Appetite Suppressant

We present a case report indicating that the administration of phentermine, an appetite suppressant with sympathomimetic activity, can provoke an intracerebral hemorrhage. A 48-year-old woman with no previously established cerebrovascular risk fa ctors and who had taken phentermine for 30 days developed sudden-onset left hemiparesis. Brain magnetic resonance imaging revealed an acute intracerebral hemorrhage involving the right thalamus. This case indicates that physicians should be aware of the relevant cause of medication history including appetite suppressants in young patients with an acute intracerebral hemorrhage.

Safety of Anti-Obesity Drugs Approved for Long-Term Use

Because of the widespread use of ant-obesity medications, bariatricians need to be aware not only of common adverse events but also uncommon serious events in the pharmacotherapy of obesity. Safety and tolerability must be considered in selecting the drug, titrating the dosage, and monitoring patients. In Korea, orlistat and lorcaserine are the two anti-obesity drugs that can be used for long-term treatment, and in the US, liraglutide, phentermine/topiramate, and naltrexone/bupropion have been recently approved. In general, all of these drugs have very good safety and tolerability profiles. Common adverse events of these drugs are well understood, and they can be coped with or prevented by adjusting the dosage properly. In addition, patients can recover from serious events by stopping the medication. However, there are other serious side effects that need to be monitored for. These include liver injury, acute kidney injury, and pancreatitis for orlistat; valvulopathy for lorcaserine; thyroid C-cell pathology and pancreatitis for liraglutide; metabolic acidosis, urolithiasis, acute angle closure glaucoma, and teratogenic effects for phentermine/topiramate; and severe nausea and heart disease for naltrexone/bupropion.

Phentermine and topiramate combination for chronic weight management: a review.

Obesity is a major public health concern and one of the leading preventable causes of death worldwide. It has manifold adverse health consequences, potentially involving all major organ systems thus leading to a reduced life expectancy. The long-term successful management of obesity remains a herculean task and invariably requires a multifaceted approach including lifestyle and behavioral modification, increased physical activity, and adjunctive pharmacotherapy and bariatric surgery. However, effective pharmacological options are limited because of the previous history of several failed agents as well as the fact that presently available agents are few, and utilized only as monotherapy. The recent Food and Drug Administration (FDA) approval of the fixed drug combination of phentermine and extended release topiramate marks the first FDA approved combination pharmacotherapeutic agent for obesity. This review details the various pharmacological aspects of the use of phentermine and topiramate combination along with the results of clinical trials done so far and also the present role of this combination in the management of obesity. Beyond the significant improvement in weight, the findings from various clinical trials also show improvement in metabolic and glycemic parameters, blood pressure, and lipid profile suggesting its added utility in cardiovascular risk modification. The acceptability of this combination would usher in a new era in the pharmacotherapy of obesity that utilizes combination therapy to improve efficacy, enhance synergism and concurrently minimize the risk of adverse effects. As with any newly marketed drug, there may be yet-unknown benefits and risks associated with this combination, which would be known only after its long-term use.

Effects of anti-obesity drugs, phentermine and mahuang, on the behavioral patterns in Sprague-Dawley rat model / 한국실험동물학회지

According to WHO global estimates from 2008, more than 1.4 billion adults were overweight and among them, over 200 million men and 300 million women were obese. Although the main treatment modalities for overweight and obese individuals remain dieting and physical exercise, the synthetic anti-obesity medications have been increasingly used due to their perceived convenience. Generally, anti-obesity medications are classified as appetite suppressants or fat absorption blockers. In the present study, we examined the adverse side-effects in respect of behavior changes of phentermine and Ephedra sinica (mahuang) that are anti-obesity drugs currently distributed to domestic consumers. Phentermine is mainly classified as an anorexing agent and mahuang a thermogenic agent. Because phentermine and mahuang are considered to display effectiveness through the regulation of nerve system, their potential influences of on behavioral changes were examined employing animal experiments. From the results of experiments testing locomotor activity through the use of treadmill, rota-rod, and open field system, phentermine and mahuang were commonly revealed to induce behavioral changes of rats by reducing a motor ability, an ability to cope with an external stimulus, and a sense of balance or by augmenting wariness or excitement. These adverse effects of phenternime and mahuang in behavioral changes need to be identified in humans and anti-obesity medications such as phentermine and mahuang should be prescribed for only obesity where it is anticipated that the benefits of the treatment outweigh their potential risks.

Pharmacotherapy for Obesity

Obesity is an important risk factor for metabolic disease and various cancers. Treatments of obesity include lifestyle intervention, pharmacotherapy, and bariatric surgery. If weight loss with lifestyle intervention is only modest, pharmacotherapy might be needed. Pharmacotherapy agents can be grouped by treatment period as short term or long term use agent. Several sympathomimetic drugs such as benzphetamine, diethylpropion, phendimetrazine and phentermine, are approved for short term treatment due to their safety issues. For long term treatment, orlistat, lorcaserin, and combination of phentermine/topiramate are approved by U.S. Food and Drug Administration (FDA). Orlistat partially blocks intestinal digestion of fat, therefore producing weight loss. Lorcaserin is a serotonin 2C receptor agonist. The combination of phentermine/topiramate produces a mean weight loss of 8-10 kg. Side effects of each drug are quite different. For obesity patient, side effects are important factor when choosing drugs. The goal of this article is to review currently available anti-obesity drugs.

Two Cases of Intoxication with Phentermine

Phentermine has been widely used as an appetite suppressant since 2004 in Korea. The authors experienced two cases of acute phentermine overdose and report with the literature review. A 36-year-old man and a 24-year-old woman presented together to the emergency department with taking 13 tablets (390 mg) of phentermine 16 hours ago. They had tachycardia, hypertension and complained visual symptoms, nausea, insomnia and anxiety. These symptoms were resolved by conservative management.

Two Cases of Intoxication with Phentermine

Phentermine has been widely used as an appetite suppressant since 2004 in Korea. The authors experienced two cases of acute phentermine overdose and report with the literature review. A 36-year-old man and a 24-year-old woman presented together to the emergency department with taking 13 tablets (390 mg) of phentermine 16 hours ago. They had tachycardia, hypertension and complained visual symptoms, nausea, insomnia and anxiety. These symptoms were resolved by conservative management.

Nuevas drogas en el tratamiento de la obesidad y el sobrepeso / New drugs for the treatment of obesity and overweight / Novas drogas no tratamento da Obesidade e Sobrepeso

a obesidad y el sobrepeso se asocian con un mayor riesgo de mortalidad global y de padecer numerosas patologías crónicas, y son muy difíciles de tratar. Es por esto que la implementación de medidas farmacológicas seguras y eficaces reviste una suprema importancia. La lorcaserina y la combinación fentermina/topiramato son nuevas opciones farmacológicas aprobadas en el año 2012 por la FDA (Food and Drugs Administration de los Estados Unidos), a pesar de su compleja forma de administración, y los requerimientos de un programa de entrenamiento y de monitoreo de postmarketing. En el artículo se describen las nuevas drogas aprobadas, sus mecanismos de acción, efectos adversos, características farmacocinéticas su uso en situaciones especiales, y los inconvenientes con las drogas previamente aprobadas y que fueron retiradas del mercado.Palabras clave: obesidad, sobrepeso, topiramato, fentermina, lorcaserin

besity and overweight are associated with an increased risk of overall mortality and the development of many chronic diseases, and they are very difficult to treat. That is why the implementation of safe and effective pharmacological measures is of paramount importance. Lorcaserin and the combination of phentermine/topiramate are two new pharmacological therapies for chronic weight management. They were approved in 2012 by the U.S. Food and Drug Administration, despite concerns over its complex form of administration and the requirement of a training and post-marketing surveillance program.This article describes newly approved drugs, their mechanisms of action, side effects, pharmacokinetics, and their use in special situations, along with the drawbacks of previously approved drugs that were withdrawn from the market.

A obesidade e o sobrepeso são associados a um maiorrisco de mortalidade global e ao padecimento de numerosaspatologias crônicas, e são muito difícies de tratar. É poristo que a implementação de medidas farmaco lógicasseguras e eficazes possui uma suprema importância.A lorcaserina e a combinação fentemina/topiramato sãonovas opções farmacológicas aprovadas no ano 2012pela FDA (Food and Drugs Administration de los EstadosUnidos), apesar da sua complexa forma de administração, eos requerimentos de um programa de treinamento e demonitoramento de postmarketing. No artigo estão descritas as novas drogas aprova das,seus mecanismos de ação, efeitos adversos, característicasfarmacocinéticas, seu uso em situações especiais, e osinconvenientes com as drogas previamente aprovadas eque foram retiradas do mercado.

Postmarketing Surveillance Study of the Efficacy and Safety of Phentermine in Patients with Obesity / 가정의학회지

BACKGROUND: Obesity is a complex problem that is now considered a chronic metabolic disease. In Korea, phentermine has been widely used for the treatment of obesity in the primary care setting since 2004. However, there have been very few studies on the safety and efficacy of phentermine. To investigate the safety and efficacy of this drug, a postmarketing surveillance study was performed. METHODS: A total of 795 patients with obesity (body mass index > or = 25 kg/m2) were enrolled from 30 primary care centers in Korea from September 2006 to November 2007. Patients were examined to ascertain safety and efficacy at 4-, 8-, and 12-week intervals. The criterion for efficacy was defined as a weight loss > or = 5% of body weight. RESULTS: Of the 795 enrolled patients, 735 (92.5%) were evaluated in safety assessments and 711 (89.4%) was included in efficacy assessments. A total of 266 adverse events (AEs) were reported by 218 patients (30.6%), and no serious AEs were reported. Among 711 patients, 324 patients (45.6%) lost > or = 5% of their body weight. The mean weight loss was 3.8 +/- 4.0 kg. CONCLUSION: AEs are commonly associated with phentermine, even though phentermine is effective for weight loss and relatively well-tolerated.

Phentermine, Sibutramine and Affective Disorders

A safe and effective way to control weight in patients with affective disorders is needed, and phentermine is a possible candidate. We performed a PubMed search of articles pertaining to phentermine, sibutramine, and affective disorders. We compared the studies of phentermine with those of sibutramine. The search yielded a small number of reports. Reports concerning phentermine and affective disorders reported that i) its potency in the central nervous system may be comparatively low, and ii) it may induce depression in some patients. We were unable to find more studies on the subject; thus, it is unclear presently whether phentermine use is safe in affective disorder patients. Reports regarding the association of sibutramine and affective disorders were slightly more abundant. A recent study that suggested that sibutramine may have deleterious effects in patients with a psychiatric history may provide a clue for future phentermine research. Three explanations are possible concerning the association between phentermine and affective disorders: i) phentermine, like sibutramine, may have a depression-inducing effect that affects a specific subgroup of patients, ii) phentermine may have a dose-dependent depression-inducing effect, or iii) phentermine may simply not be associated with depression. Large-scale studies with affective disorder patients focusing on these questions are needed to clarify this matter before investigation of its efficacy may be carried out and it can be used in patients with affective disorders.

A Case of Phentermine Hydrochloride Induced Acute Myopia and Acute Angle Closure

PURPOSE: To describe a case of bilateral acute myopia and acute angle-closure associated with phentermine hydrochloride, a drug used for obesity treatment. CASE SUMMARY: A 25-year-old woman visited our hospital with blurry vision and ocular pain after taking phentermine hydrochloride for three weeks. Manifest refraction accompanied myopic shift in the both eyes, slit-lamp examination showed forward displacement of the lens-iris diaphragm and fundus examination revealed retinal folds. Suspecting phentermine hydrochloride induced acute myopia and acute angle closure, discontinuation of the drug and administration of cycloplegic agents and antiglaucomatic agent successfully resolved the symptoms. CONCLUSIONS: Although the exact mechanism is unknown, phentermine hydrochloride may generate ciliochoroidal effusion and ciliary edema, lead to acute myopia and acute angle closure resulting from forward displacement of the lens-iris diaphragm.

Pulmonary Hypertension Associated with Use of Phentermine

Weight-control drugs (known as anorexigens) such as fenfluramine have been linked with pulmonary hypertension in previous reports. In our case, a 29 year old woman was admitted for shortness of breath and was diagnosed with pulmonary hypertension. Three months ago, she had been taking phentermine for five weeks. Other factors that might have contributed to the development of pulmonary hypertension were excluded. With treatment, her symptoms improved. This is the first case that can suggest a possible connection between phenermine single medication with pulmonary hypertension. Phentermine has been considered a relatively safe drug to treat obesity, and further investigation is needed to decide the safety and dosage of phentermine.

Effects on Weight Reduction and Safety of Short-Term Phentermine Administration in Korean Obese People

The phentermine, an appetite suppressant, has been widely applied in Korea since 2004. However, there have been relatively few reports about the efficacy and the safety of phentermine in Korea. The aim of this study is to verify the effect of phentermine on weight reduction and the safety in Korean patients. This randomized, double-blind, placebo- controlled study had been performed between February and July, 2005, in Seoul on 68 relatively healthy obese adults whose body mass index was 25 kg/m2 or greater. They received phentermine-HCl 37.5 mg or placebo once daily with behavioral therapy for obesity. The primary endpoints were the changes of body weight and waist circumference from the baseline in the intention-to-treat population. Mean decrease of both body weight and waist circumference in phentermine-treated subjects were significantly greater than that of placebo group (weight: -6.7 +/- 2.5 kg, p < 0.001; waist circumference: -6.2 +/- 3.5 cm, p < 0.001). Significant number of subjects in phentermine group accomplished weight reduction of 5% or greater from the baseline and 10% or more (p < 0.001). There were no significant differences in systolic and diastolic blood pressure between the groups (p = 0.122 for systolic BP; p = 0.219 for diastolic BP). Dry mouth and insomnia were the only statistically significant adverse events that occurred more frequently in phentermine group. Most side effects of phentermine were mild to moderate in intensity. Short-term phentermine administration induced significant weight reduction and reduction of waist circumference without clinically problematic adverse events on relatively healthy Korean obese people.