Important things to keep in mind from a review of drugs used to treat obesity are as follows:
Multiple antiobesity drugs (AOMs) with indications to treat individuals with a body mass index (BMI) of ≥30 kg/m2 or ≥27 kg/m2 as well as weight-related comorbidities including type 2 diabetes, hypertension, or dyslipidemia have been approved by the Food and Drug Administration (FDA). Adolescents with a BMI at or above the 95% percentile for their age and gender who are obese and between the ages of 12 and 17 should also be treated with AOMs.
Based on how they work, AOMs are divided into three primary categories: nutrient-stimulated hormone-based drugs, centrally acting medications, and intra-gastrointestinal (intra-GI) medications.
The sole FDA-approved intra-GI medication, orlistat, functions by preventing the stomach and small intestine from breaking down and absorbing about 30% of dietary fat. The American Gastroenterological Association advises against using orlistat to treat obesity, despite the fact that the majority of guidelines support its use. This is because orlistat has a little impact on weight loss and has negative GI side effects. Orlistat has a negligible impact on weight loss, but it also lowers glycated hemoglobin (HbA1c), low-density lipoprotein (LDL) cholesterol, systolic blood pressure (BP), and has been linked to the prevention of type 2 diabetes.
Phentermine, phentermine-topiramate, and naltrexone-bupropion are examples of AOMs that operate centrally. These drugs work in the brain through a variety of pathways that decrease hunger.
Only short-term usage, up to three months, is permitted for phentermine, and patients without cardiovascular problems are advised to use it. Few or no major adverse effects happened in the studies that are now available that lasted six months or more, despite the fact that few research have assessed the safety and efficacy of phentermine beyond three months. The least priced AOM for individuals without insurance is phentermine.
A 10% weight loss can be attained and maintained with long-term phentermine-topiramate use, and observational evidence has not revealed any link between this AOM and adverse cardiovascular events. Since bupropion is known to raise blood pressure, BP should be regularly monitored during the start of treatment and any dose escalation while using naltrexone-bupropion. Weight reduction with this combination is better when paired with rigorous behavioral therapy.
There are now three AOMs based on nutrition-stimulated hormones that have FDA approval: tirzepatide, semaglutide, and liraglutide. Liraglutide has been demonstrated to reduce HbA1c and significant adverse cardiovascular events in patients with type 2 diabetes, in addition to causing weight loss.
More weight losses have been observed with semaglutide and tirzepatide than with other AOMs, such as liraglutide. Furthermore, these medications are linked to better cardiometabolic outcomes, such as waist circumference, blood pressure, and HbA1c. Additionally, semaglutide has been demonstrated to lessen the symptoms of heart failure and enhance the distance covered on a 6-minute walk in individuals whose ejection fraction is intact.
All AOMs are authorized for use as supplemental treatments in conjunction with dietary and exercise changes, such as cutting back on calories. To enhance results, the US Preventive Services Task Force suggests using behavioral therapy in addition to AOMs.
Resistance training should be incorporated into patient care to reduce loss of lean body mass and improve functional strength and mobility. When an older adult has reduced lean body mass as a result of aging, AOMs should be taken cautiously.
Poor AOM adherence and weight increase are common side effects of stopping medication, according to real-world studies. To decide how long to prescribe a medicine, clinicians should use shared decision making. This includes halting the medication and closely monitoring weight, utilizing intermittent therapy, or continuing the lowest effective dose.