Pharmacotherapy for adults with overweight and obesity: a systematic review and network meta-analysis of randomised controlled trials.

BACKGROUND: Pharmacotherapy provides an option for adults with overweight and obesity to reduce their bodyweight if lifestyle modifications fail. We summarised the latest evidence for the benefits and harms of weight-lowering drugs. METHODS: This systematic review and network meta-analysis included searches of PubMed, Embase, and Cochrane Library (CENTRAL) from inception to March 23, 2021, for randomised controlled trials of weight-lowering drugs in adults with overweight and obesity. We performed frequentist random-effect network meta-analyses to summarise the evidence and applied the Grading of Recommendations Assessment, Development, and Evaluation frameworks to rate the certainty of evidence, calculate the absolute effects, categorise interventions, and present the findings. The study was registered with PROSPERO, CRD 42021245678. FINDINGS: 14 605 citations were identified by our search, of which 132 eligible trials enrolled 48 209 participants. All drugs lowered bodyweight compared with lifestyle modification alone; all subsequent numbers refer to comparisons with lifestyle modification. High to moderate certainty evidence established phentermine-topiramate as the most effective in lowering weight (odds ratio [OR] of ≥5% weight reduction 8·02, 95% CI 5·24 to 12·27; mean difference [MD] of percentage bodyweight change -7·98, 95% CI -9·27 to -6·69) followed by GLP-1 receptor agonists (OR 6·33, 95% CI 5·00 to 8·00; MD -5·79, 95% CI -6·34 to -5·25). Naltrexone-bupropion (OR 2·69, 95% CI 2·10 to 3·44), phentermine-topiramate (2·40, 1·68 to 3·44), GLP-1 receptor agonists (2·22, 1·74 to 2·84), and orlistat (1·71, 1·42 to 2·05) were associated with increased adverse events leading to drug discontinuation. In a post-hoc analysis, semaglutide, a GLP-1 receptor agonist, showed substantially larger benefits than other drugs with a similar risk of adverse events as other drugs for both likelihood of weight loss of 5% or more (OR 9·82, 95% CI 7·09 to 13·61) and percentage bodyweight change (MD -11·40, 95% CI -12·51 to -10·29). INTERPRETATION: In adults with overweight and obesity, phentermine-topiramate and GLP-1 receptor agonists proved the best drugs in reducing weight; of the GLP-1 agonists, semaglutide might be the most effective. FUNDING: 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University.

Comparison of the Efficacy of Anti-Obesity Medications in Real-World Practice.

Purpose: Anti-obesity medications (AOMs), along with lifestyle interventions, are effective means of inducing and maintaining weight loss in patients with obesity. Although the efficacy of AOMs has been reported, there have been no direct comparisons of these drugs. Therefore, in the present study, we aimed to compare the efficacy of all the AOMs available in Korea in a real-world setting. Patients and Methods: The body weight and composition of 205 adults treated with phentermine, phentermine/topiramate, liraglutide, naltrexone/bupropion, lorcaserin, or orlistat for at least 6 months were analyzed at 2 month intervals. The prevalence of the achievement of a ≥5% weight loss and the changes in body composition were compared between participants using each AOM at each visit. Results: A total of 132 (64.4%) participants achieved ≥5% weight loss within 6 months (prevalence of ≥5% weight loss after 6 months: phentermine, 87.2%; phentermine/topiramate, 67.7%; liraglutide, 58.1%; naltrexone/bupropion, 35.3%; lorcaserin, 75%; orlistat, 50%). At each visit, after adjustment for age, sex, and baseline body weight, phentermine use was associated with a significantly higher prevalence of ≥5% weight loss than the use of the other AOMs, except for liraglutide. There were significant differences in the body weight, body mass index and body fat mass among the AOM groups by visit (P for interaction <0.05), but not in their waist circumference, skeletal muscle mass, percentage body fat, or visceral fat area. Conclusion: All the AOMs were effective at inducing and maintaining weight loss, in the absence of significant changes in muscle mass, over a 6 month period, and the short-term use of phentermine and the long-term use of phentermine/topiramate or liraglutide would be practical choices for the treatment of obesity. However, further, large-scale studies are necessary to confirm these findings.

Potential drug-drug interactions with phentermine among long-term phentermine consumers: A retrospective analysis.

BACKGROUND: Phentermine is an internationally recognised amphetamine derivative with significant appetite-suppressing properties. The drug is indicated for the short-term management of obesity, as the long-term (LT) use of phentermine may potentially be associated with severe cardiovascular side-effects, abuse and dependence. The LT use hereinafter describes periods exceeding 12 consecutive weeks. This use may also be associated with potential drug-drug interactions (PDDIs), which may result in adverse drug reactions (ADRs). The literature reports that phentermine is often prescribed LT and for several other off-label indications, increasing the risk for individuals to experience adverse drug events (ADEs) and drug-drug interactions (DDIs). There are, to our knowledge, no South African (SA) studies investigating the prevalence of co-prescribing LT phentermine with drugs that may potentially cause DDIs. OBJECTIVE: To determine the prevalence of mild, moderate and severe DDIs with phentermine use when the duration of therapy in private healthcare exceeded 12 consecutive weeks. METHODS: A cross-sectional drug utilisation review (DUR) was done by using data obtained from a SA pharmacy benefit management (PBM) company's database. Retrospective data of medicine claims for phentermine, from 1  January 2015 to 31  December 2019, were extracted for analysis. The number of days phentermine was supplied was used to identify the study population, in other words, those patients who received the drug LT. A drug interaction checker (Drugs.com) was used to identify potential mild, moderate and severe DDIs when using phentermine and co-prescribed drugs concurrently. RESULTS: A total of 889 patients received phentermine LT. The top 20 drugs identified as being frequently co-prescribed in this study population demonstrated no mild PDDI, 15 (75%) moderate PDDIs and 5 (25%) severe PDDIs. The most common co-prescribed drug in the moderate group was dextromethorphan (n=282, 31.72%) and the least co-prescribed was formoterol (n=52, 5.85%). Among the drug group 'severe PDDIs', tramadol (n=416, 46.79%) was most frequently prescribed, whereas phenylpropanolamine (n=69, 7.76%) was the least prescribed to patients in this group. CONCLUSION: There are patients who receive LT phentermine therapy despite the potential severe consequences that may result. These patients may receive concomitant therapy with phentermine and other pharmaceutical constituents, which may potentially cause DDIs, more specifically, moderate and severe DDIs. As such, these patients are not only confronted with the consequences of DDIs but are also at risk to experience ADRs as the residual effect of PDDIs.

Pharmacokinetic and pharmacodynamic interaction of DWP16001, a sodium-glucose cotransporter-2 inhibitor, with phentermine in healthy subjects.

BACKGROUND: DWP16001, a sodium-glucose cotransporter-2 inhibitor, has shown promise for improving blood glucose control and facilitating weight loss. Co-administration with phentermine could enhance these effects. So, we aimed to evaluate the pharmacokinetic (PK) and pharmacodynamic (PD) interactions of DWP16001 and phentermine. METHODS: We conducted a randomized, open-label, 3-treatment, 6-sequence, 3-period crossover study involving 24 healthy adults. Participants received either DWP16001 (2 mg), phentermine (37.5 mg), or a combination of both once daily for 7 days. Blood samples, urine samples, and body weights were collected to evaluate the PK and PD. RESULTS: The PK of the combination was found to be similar to that of the monotherapy. The geometric mean ratio (GMR) of Cmax,ss, and AUCtau,ss were 0.98 and 1.00, respectively, for DWP16001, and 1.01 and 0.94, respectively, for phentermine. Co-administration did not significantly affect the 24-hour urinary glucose excretion compared to DWP16001 monotherapy, and the GMR was 0.90. Participants tended to experience greater weight loss in the combination therapy group, and all demonstrated good tolerance. CONCLUSIONS: Our findings indicate that there were no significant interactions during co-administration. These results suggest that the combination of DWP16001 and phentermine may be safe and effective for the treatment of obesity and diabetes. CLINICAL TRIAL REGISTRATION: NCT05321732.

[Renal Damage and Obesity: a Silent Pairing].

Obesity is recognized as a true chronic disease and an independent risk factor for kidney disease. In particular, a correlation was observed between obesity and the development of focal segmental glomerulosclerosis. The clinical consequences of obesity on the kidney can include albuminuria, nephrotic syndrome, nephrolithiasis, and increased risk of development and progression of renal failure. Conventional therapy, which includes low-calorie diet, exercise, lifestyle changes, and drug therapy, including GLP1-RA, phentermine, phentermine/topiramate, bupropion/naltrexone, orlistat, is not always able to achieve the desired results and above all does not guarantee stabilization of body weight over time. On the other hand, bariatric surgery is giving excellent results in terms of efficacy and duration. Bariatric surgery techniques that are generally divided into restrictive, malabsorptive, and mixed are not free from possible metabolic complications such as anemia, vitamin deficiency, and stones. However, they are able to ensure a good maintenance of weight loss obtained with disappearance or reduction of the incidence and severity of comorbidities related to obesity.

Assessment of the Risk Evaluation and Mitigation Strategy (REMS) for Phentermine-Topiramate to Prevent Exposure During Pregnancy.

BACKGROUND: The U.S. Food and Drug Administration approved phentermine-topiramate for obesity in 2012 and required a Risk Evaluation and Mitigation Strategy (REMS) to prevent prenatal exposure. No such requirement was introduced for topiramate. OBJECTIVE: To evaluate the rate of prenatal exposure, contraceptive use, and pregnancy testing among patients with phentermine-topiramate compared with topiramate or other antiobesity medications (AOMs). DESIGN: Retrospective cohort study. SETTING: Nationwide health insurance claims database. PARTICIPANTS: Females aged 12 to 55 years with no infertility diagnosis or sterilization procedure. Patients with other indications for topiramate were excluded to identify a cohort that was likely treated for obesity. MEASUREMENTS: Patients initiated use of phentermine-topiramate, topiramate, or an AOM (liraglutide, lorcaserin, or bupropion-naltrexone). Pregnancy at treatment initiation, conception during treatment, contraceptive use, and pregnancy testing outcomes were ascertained. Measurable confounders were adjusted for, and extensive sensitivity analyses were done. RESULTS: A total of 156 280 treatment episodes were observed. Adjusted prevalence of pregnancy at treatment initiation was 0.9 versus 1.6 per 1000 episodes (prevalence ratio, 0.54 [95% CI, 0.31 to 0.95]) for phentermine-topiramate versus topiramate. The incidence rate of conception during treatment was 9.1 versus 15.0 per 1000 person-years (rate ratio, 0.61 [CI, 0.40 to 0.91]) for phentermine-topiramate versus topiramate. Both outcomes were similarly lower for phentermine-topiramate compared with AOM. Prenatal exposure was marginally lower in topiramate users compared with AOM users. Approximately 20% of patients in all cohorts had at least 50% of treatment days covered by contraceptives. Few patients had pregnancy tests before treatment (≤5%), but this was more common among phentermine-topiramate users. LIMITATIONS: Outcome misclassification; unmeasured confounding due to lack of prescriber data to account for possible clustering and spillover effects. CONCLUSION: Prenatal exposure seemed to be significantly lower among phentermine-topiramate users under the REMS. Pregnancy testing and contraceptive use appeared to be inadequate for all groups, which deserves attention to prevent the remaining potential exposures. PRIMARY FUNDING SOURCE: None.

Real-World Experience of the Efficacy and Safety of Phentermine Use in Adolescents: A Case Series.

Background: Pharmacotherapy has emerged as a practical option for weight management in pediatrics. This study aims to assess the effectiveness and safety of phentermine use in pediatric patients with obesity. Methods: We performed a retrospective single-center analysis of patients younger than or equal to 18 years of age, over 10 years, who underwent phentermine treatment and recommended lifestyle changes. We evaluated efficacy by the change in the percent of the 95th percentile for BMI (%BMIp95). We deemed a 5% decrease in %BMIp95 as a favorable outcome. Results: We identified 30 pediatric patients who were treated with phentermine. The cohort was primarily female, 63% white, with a mean (standard deviation) baseline age of 15.63 (1.97) years. The average duration of treatment was 10 months, with a period ranging from 2 weeks to 2 years. The average %BMIp95 at the start of treatment was 137%, and that at the time of analysis was 122%, with a mean reduction of 15%. Five patients, 17%, experienced side effects that resolved after dose reduction or discontinuing phentermine. Conclusions: Phentermine monotherapy is an effective and safe means for weight loss in pediatric patients when combined with lifestyle interventions. Twenty-one of 30 (70%) patients achieved at least a 5% decrease in %BMIp95 within a mean duration of treatment of 10 months. We noted no severe adverse events.

Topiramate Utilization After Phentermine/Topiramate Approval for Obesity Management: Risk Minimization in the Era of Drug Repurposing.

INTRODUCTION: The US FDA required a Risk Evaluation and Mitigation Strategy (REMS) for phentermine/topiramate, an anti-obesity medication, to prevent congenital malformations. No REMS is required for single-ingredient topiramate, which may be used off-label for the same purpose. OBJECTIVE: The aim of this study was to evaluate the impact of phentermine/topiramate approval in 2012 on subsequent topiramate use among patients with obesity. METHODS: We used a national insurance claims database to conduct an interrupted time-series study (2009-2015). Enrollees aged 18-65 years in each examined calendar quarter had full insurance benefits during that quarter and the preceding 6 months. We required patients to have an obesity diagnosis and no other conditions warranting topiramate use. We calculated topiramate or comparator drug (atorvastatin, metformin) initiation rates and evaluated changes in trends before and after 2012 (transition period). RESULTS: Among topiramate users, 80% were female, and demographic characteristics remained consistent during the study period. Between 2009 and 2011, the topiramate initiation rate (95% confidence interval) among patients with obesity was 0.85 (0.73-0.98) per 1000 patients, with no significant upward or downward trend. In the first quarter of 2013, this rate had increased more than 2.5-fold (change: + 1.36 [1.19-1.52]). Metformin and atorvastatin initiation rates did not change. Topiramate initiation rates were threefold higher than phentermine/topiramate rates during the post-approval period. CONCLUSION: Phentermine/topiramate approval was associated with increased topiramate use among patients with obesity. Prescribers are encouraged to enhance patient education and monitoring in such clinical use since topiramate prescribing information, compared with REMS for phentermine/topiramate, has less emphasis on preventing prenatal exposure.

Phentermine/Topiramate: Pediatric First Approval.

Phentermine/topiramate extended-release capsule (Qsymia®) is a fixed-dose combination of phentermine and topiramate, which is being developed by VIVUS (a subsidiary of Icahn Enterprises) for the treatment of obesity, sleep apnoea syndrome, type 2 diabetes mellitus and non-alcoholic steatohepatitis (NASH). The once-daily formulation of phentermine (a sympathomimetic amine) and topiramate is designed to combat obesity by decreasing appetite and increasing satiety. In July 2022, phentermine/topiramate received its first approval in the USA, as an adjunct to a reduced-calorie diet and increased physical activity, for chronic weight management in pediatric patients aged ≥ 12 years with BMI in the 95th percentile or greater standardized for age and sex. Phentermine/topiramate is approved in the US and South Korea for obesity in adults. Clinical development of phentermine/topiramate for sleep apnoea syndrome and type-2 diabetes in obese patients and preclinical development for NASH is ongoing in the US. This article summarizes the milestones in the development of phentermine/topiramate leading to this pediatric first approval for chronic weight management in adolescents.

Effect of Phentermine on Hepatic Steatosis in Bariatric Surgery: A Pilot Study.

OBJECTIVE: Hepatic steatosis is associated with increased surgical complications in bariatric surgery patients. We aimed to evaluate the effect of phentermine in reducing hepatic steatosis, adipose tissue, and surgical complications in patients undergoing bariatric surgery. METHODS: This was a two-arm, double-blind, randomized, controlled pilot trial of 64 adult subjects with BMI >35 kg/m2 selected for bariatric surgery randomized into phentermine group (15 mg once daily) or placebo group for 8 weeks. Both groups adhered to a hypocaloric diet (500 calories/day) and an individualized exercise program. The primary endpoint was reducing the frequency of hepatic steatosis measured by ultrasound and reducing adipose tissue through fat mass in total kilograms or percentage. Key secondary points were the prevalence of surgical complications. Baseline and final biochemical parameters and blood pressure too were assessments. RESULTS: In the phentermine group, the frequency of hepatic steatosis decreased by 19%, and the percentage of patients with a normal ultrasound increased from 9% to 28% (p = 0.05). Likewise, the decrease in fat mass in kilograms was more significant in the phentermine group (56.1 kg vs. 51.8 kg, p = 0.02). A significant reduction in the HOMA-IR index was observed regardless of weight loss. No differences in surgical complications were observed between groups. Phentermine was well-tolerated; no differences were observed in the frequency of adverse events between the groups. CONCLUSIONS: Phentermine decreased the proportion of individuals with hepatic steatosis by 19% and promoted a more significant fat mass loss in kilograms among candidates for bariatric surgery.

Intensive management of obesity in people with Prader-Willi syndrome.

PURPOSE: Prader-Willi syndrome (PWS) is characterised by childhood-onset hyperphagia and obesity however limited data are available to guide treatment of obesity in this population. We aimed to evaluate the safety, tolerability, and efficacy of intensive medical weight loss interventions (very-low-energy diets [VLED] and/or pharmacotherapy) in individuals with PWS attending a specialist obesity management service. METHODS: A retrospective audit was undertaken of individuals with PWS attending the Austin Health Weight Control Clinic between January 2010-April 2021. Main outcome measures were weight outcomes, duration of use, and adverse effects. RESULTS: Data were available for 18 patients, of whom 15 were treated with intensive weight loss interventions. Median (interquartile range, IQR) age at baseline was 20 years (19-32) with median body weight 90 kg (75-118) and BMI 37 kg/m2 (30-51). Median weight loss during VLED (n = 7) was 14 kg (1-20 kg) over 60 weeks. Median weight loss with phentermine-topiramate (n = 7) was 17 kg (IQR 9-19 kg) over 56 weeks. Median weight loss with liraglutide 0.6-3 mg (n = 7), prescribed with topiramate in 3 individuals, was 9 kg (2-14 kg) over 96 weeks. Naltrexone-bupropion resulted in weight loss in 2 of 4 individuals. Thirteen individuals achieved ≥10% weight loss but only 5 individuals maintained ≥10% weight loss at last follow-up. Five individuals discontinued pharmacotherapy due to adverse effects. CONCLUSIONS: VLED and pharmacotherapy can achieve substantial weight loss in some individuals with PWS though non-adherence results in substantial weight regain. Adverse effects were ascribed to phentermine and topiramate, whereas liraglutide was well-tolerated in this population.

Prevalence of Antiobesity Treatment and Weight-Inducing Antihyperglycemic Agents Among Patients With Type 2 Diabetes in the United States.

PURPOSE: Nearly 90% of individuals with type 2 diabetes mellitus (T2DM) are either overweight or obese, placing them at high risk of microvascular and macrovascular complications. The main objective of this study was to assess the use of antiobesity medications and antihyperglycemic agents that produce weight gain among patients with T2DM who qualify for National Institutes of Health guideline-recommended pharmacologic weight loss therapy. METHODS: This study used the 2005-2006 through 2015-2016 biannual cycles of the National Health and Nutrition Examination Survey and included adults aged ≥20 years who reported a diagnosis of T2DM and who qualified for antiobesity treatment (defined as a body mass index ≥27 kg/m2) at the time of physical examination. Antiobesity medication use was defined as use of orlistat, phentermine, diethylpropion, lorcaserin, phentermine/topiramate, bupropion/naltrexone, or liraglutide. Use of weight-inducing antihyperglycemic agents was defined as use of sulfonylureas, thiazolidinediones, or insulin (any type), either alone or in combination with any other antihyperglycemic agent regardless of effect on weight. FINDINGS: Among adults with T2DM who qualified for antiobesity treatment (N = 2910), only 40 participants (2.2%; 95% CI, 1.5-3.3) were on pharmacologic antiobesity treatment within 30 days of survey interview. The only antiobesity medications identified were liraglutide (n = 34 [1.9%]), phentermine (n = 4 [0.2%]), orlistat (n = 1 [0.1%]), and phentermine/topiramate (n = 1 [0.0%]). Among those who were on antihyperglycemic treatment (n = 2401), 1661 (66%; 95% CI, 63.1-68.8) were on weight-inducing antihyperglycemic agents; however, a downward trend in the use of these agents over time was observed (from 78.4% in 2005-2006 to 53.3% in 2015-2016; P < 0.0005). IMPLICATIONS: This is the first national epidemiologic study evaluating the use of antiobesity medications and weight-inducing antihyperglycemic agents among patients with T2DM who qualify for weight loss therapy. This study documents that patients are not on guideline-directed weight loss therapy. Furthermore, weight loss goals are likely compromised by 66% of individuals being on weight-inducing antihyperglycemic therapy. Use of antiobesity medications could play a significant role in promoting weight loss and potentially lead to a healthier lifestyle, which could reduce microvascular and macrovascular complications. Stronger recommendations in using guideline-directed therapy in obesity complicated by T2DM are necessary.

Three- and six-month efficacy and safety of phentermine in a Mexican obese population.

OBJECTIVE: Mexico has the second largest prevalence of obesity among adults worldwide, a condition especially affecting the low-income population. There is a pressing need to improve therapeutic options for weight loss. Phentermine is an old and low-cost agent given as an adjuvant therapy for obesity for a 12-week period, at an initial dose of 15 mg or 30 mg. However, there are no precise guidelines on the suitability of both the starting dose and the continuation of treatment for 6 months. The aim of this study was to evaluate the 3- and 6-month efficacy and safety of phentermine in obese Mexican patients to elucidate the aforementioned. MATERIALS AND METHODS: In this prospective, multi-center, open-label study, 932 obese adults received 15 mg or 30 mg phentermine once daily for 6 months. RESULTS: 30 mg phentermine was more effective than 15 mg phentermine in improving anthropometric variables in the 3-month follow-up, but not after completing the 6-month treatment period. Nearly 40% of 3-month non-responders reached a body weight reduction of at least 5% at 6 months. Conversely, ~ 65% and 25% of 3-month responders maintained or improved, respectively, their body weight reduction with long-term phentermine. Potential tolerance as weight regain was ~ 10% from 3 to 6 months. None of the doses increased cardiovascular risk, although mild-to-moderate adverse events were more frequent with 30 mg phentermine. CONCLUSION: 30 mg phentermine was more effective than 15 mg phentermine after 3 months, but not at 6 months of treatment. An important number of subjects could benefit following the therapy from 3 to 6 months.

Efficacy and Safety of Phentermine/Topiramate in Adults with Overweight or Obesity: A Systematic Review and Meta-Analysis.

OBJECTIVE: The study objective was to examine the association between phentermine/topiramate therapy and weight loss and adverse events in adults with overweight or obesity by meta-analysis and systematic review. METHODS: Medical Subject Headings and free-text terms were selected to search for eligible trials in PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase up to April 18, 2020. The quality of randomized controlled trials was evaluated by the Cochrane risk-of-bias tool. Meta-analysis was performed using random-effect models. RESULTS: Phentermine/topiramate therapy resulted in an average weight loss of 7.73 kg (95% CI: 6.60-8.85) in general compared with placebo. The weight loss was related to the dose of phentermine/topiramate. Compared with placebo, the average weight loss was 3.55 kg (95% CI: 2.22-4.88) for 3.75/23 mg, 7.27 kg (95% CI: 6.40-8.13) for 7.5/46 mg, and 8.25 kg (95% CI: 6.92-9.79) for 15/92 mg. For phentermine/topiramate participants in different weight-loss subgroups, the weight loss of participants with ≥5%, ≥10%, and ≥15% baseline weight loss was 3.18 (95% CI: 2.75-3.67), 5.32 (95% CI: 4.53-6.25), and 5.65 (95% CI: 3.55-9.01), respectively. Compared with placebo, the adverse events associated with the treatment mainly included dysgeusia (odds ratio [OR] = 8.86, 95% CI: 5.65-13.89), paresthesia (OR = 8.51, 95% CI: 6.20-11.67), dry mouth (OR = 6.71, 95% CI: 5.03-8.94), disturbance in attention (OR = 4.48, 95% CI: 2.39-8.41), irritability (OR = 4.10, 95% CI: 2.29-7.33), hypoesthesia (OR = 3.81, 95% CI: 1.32-11.00), constipation (OR = 2.43, 95% CI: 2.02-2.93), and dizziness (OR = 2.26, 95% CI: 1.72-2.98). Phentermine/topiramate also reduced waist circumference, blood pressure, blood sugar levels, and lipid levels. CONCLUSIONS: Phentermine/topiramate has considerable benefit in reducing body weight, and the efficacy was closely related to the dosage. However, it increased the risk of nervous system-related adverse events.

Supraventricular tachycardia with the use of phentermine: case report and review of literature.

Case: A 34-year-old woman with no significant past medical history presented to the hospital with sudden onset of palpitations with associated dyspnea and chest discomfort. She denied any similar previous episodes. Initial electrocardiogram (EKG) was consistent with a short R-P interval supraventricular tachycardia (SVT). Her transthoracic echocardiogram (TTE) revealed no structural abnormalities, TSH levels were normal, and urine drug screen was negative for any recreational drugs. However, the patient had been taking phentermine for weight loss.Discussion: The exact mechanism is not clear; however, we postulate that the sympathomimetic effects of phentermine likely contribute to SVT induction through enhanced AV nodal conduction or increased atrial ectopy. Conclusions: The only medication she was taking at home was phentermine, and the palpitations did not recur after discontinuation of the drug during follow-up. It is important to collect a thorough medication history when patients present with AV nodal reentrant tachycardia (AVNRT) or other SVT.

Long-term effects of weight-reducing drugs in people with hypertension.

BACKGROUND: This is the third update of this review, first published in July 2009. All major guidelines on treatment of hypertension recommend weight loss; anti-obesity drugs may be able to help in this respect. OBJECTIVES: Primary objectives: To assess the long-term effects of pharmacologically-induced reduction in body weight in adults with essential hypertension on all-cause mortality, cardiovascular morbidity, and adverse events (including total serious adverse events, withdrawal due to adverse events, and total non-serious adverse events).. Secondary objectives: To assess the long-term effects of pharmacologically-induced reduction in body weight in adults with essential hypertension on change from baseline in systolic and diastolic blood pressure, and on body weight reduction. SEARCH METHODS: For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to March 2020: the Cochrane Hypertension Specialised Register, CENTRAL, MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. The searches had no language restrictions. We contacted authors of relevant papers about further published and unpublished work. SELECTION CRITERIA: Randomised controlled trials of at least 24 weeks' duration in adults with hypertension that compared approved long-term weight-loss medications to placebo.  DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed risks of bias, and extracted data. Where appropriate and in the absence of significant heterogeneity between studies (P > 0.1), we pooled studies using a fixed-effect meta-analysis. When heterogeneity was present, we used the random-effects method and investigated the cause of the heterogeneity. MAIN RESULTS: This third update of the review added one new trial, investigating the combination of naltrexone/bupropion versus placebo. Two medications, which were included in the previous versions of this review (rimonabant and sibutramine) are no longer considered relevant for this update, since their marketing approval was withdrawn in 2010 and 2009, respectively. The number of included studies in this review update is therefore six (12,724 participants in total): four RCTs comparing orlistat to placebo, involving a total of 3132 participants with high blood pressure and a mean age of 46 to 55 years; one trial comparing phentermine/topiramate to placebo, involving 1305 participants with high blood pressure and a mean age of 53 years; and one trial comparing naltrexone/bupropion to placebo, involving 8283 participants with hypertension and a mean age of 62 years. We judged the risks of bias to be unclear for the trials investigating orlistat or naltrexone/bupropion. and low for the trial investigating phentermine/topiramate. Only the study of naltrexone/bupropion included cardiovascular mortality and morbidity as predefined outcomes. There were no differences in the rates of all-cause or cardiovascular mortality, major cardiovascular events, or serious adverse events between naltrexone/bupropion and placebo. The incidence of overall adverse events was significantly higher in participants treated with naltrexone/bupropion. For orlistat, the incidence of gastrointestinal side effects was consistently higher compared to placebo. The most frequent side effects with phentermine/topiramate were dry mouth and paraesthesia. After six to 12 months, orlistat reduced systolic blood pressure compared to placebo by mean difference (MD) -2.6 mm Hg (95% confidence interval (CI) -3.8 to -1.4 mm Hg; 4 trials, 2058 participants) and diastolic blood pressure by MD -2.0 mm Hg (95% CI -2.7 to -1.2 mm Hg; 4 trials, 2058 participants). After 13 months of follow-up, phentermine/topiramate decreased systolic blood pressure compared to placebo by -2.0 to -4.2 mm Hg (1 trial, 1030 participants) (depending on drug dosage), and diastolic blood pressure by -1.3 to -1.9 mm Hg (1 trial, 1030 participants) (depending on drug dosage). There was no difference in the change in systolic or diastolic blood pressure between naltrexone/bupropion and placebo (1 trial, 8283 participants). We identified no relevant studies investigating liraglutide or lorcaserin in people with hypertension. AUTHORS' CONCLUSIONS: In people with elevated blood pressure, orlistat, phentermine/topiramate and naltrexone/bupropion reduced body weight; the magnitude of the effect was greatest with phentermine/topiramate. In the same trials, orlistat and phentermine/topiramate, but not naltrexone/bupropion, reduced blood pressure. One RCT of naltrexone/bupropion versus placebo showed no differences in all-cause mortality or cardiovascular mortality or morbidity after two years. The European Medicines Agency refused marketing authorisation for phentermine/topiramate due to safety concerns, while for lorcaserin the application for European marketing authorisation was withdrawn due to a negative overall benefit/risk balance. In 2020 lorcaserin was also withdrawn from the US market. Two other medications (rimonabant and sibutramine) had already been withdrawn from the market in 2009 and 2010, respectively.

Pharmacotherapy for Weight Loss in Cirrhosis and Liver Transplantation: Translating the Data and Underused Potential.

BACKGROUND AND AIMS: Thirty percent of patients with cirrhosis are obese and the prevalence of obesity increases after transplant to >40% post-transplant. There are currently four weight loss medications approved by the FDA for treatment of obesity (orlistat, phentermine-topiramate, naltrexone-bupropion, and liraglutide). The aim of this review was to investigate the data on the use of these weight loss medications and alternative medicines in patients with cirrhosis and in liver transplant recipients (LTRs). APPROACH AND RESULTS: While there is paucity of data for these medications in patients with cirrhosis and LTRs, Liraglutide appears to be generally safe in view of its pharmacokinetic properties. Phentermine-topiramate seems to have the highest weight loss potential but special consideration should be given to neuropsychiatric disorders, cardiovascular comorbidities, and drug interactions. There are emerging data on use of alternative medicines for weight loss but more data are needed. CONCLUSIONS: The use of weight loss medications is feasible in this patient population but the decision of which medication to prescribe should be individualized based on the degree of renal and hepatic impairment, other co-morbidities, and concomitant medications.