Metformin for atypical antipsychotic-induced weight gain and glucose metabolism dysregulation: review of the literature and clinical suggestions

Management of Medication-Induced Weight Gain

Several medications can contribute to weight gain. Medication-induced weight gain can have severe health consequences leading to overweight or obesity, or exacerbation of preexisting obesity and the plethora of obesity-related comorbidities. Weight gain due to medications is potentially avoidable by prescribing medications that are either weight neutral or that lead to weight loss, when appropriate. This article reviews the common classes of medications that contribute to weight gain and discusses alternatives to consider.

Ecofriendly chromatographic methods for determination of co-prescribed drugs, olanzapine and metformin, in rat plasma

Background: Olanzapine (OLZ) is one of most recommended drugs for the treatment of schizophrenia while metformin (MET) is the most commonly used hypoglycemic agent. Aim: Development and validation of two green, sensitive and accurate chromatographic methods for the simultaneous determination of OLZ along with the co-prescribed, MET. Materials & methods: TLC-densitometric method with a developing system consisting of methylene chloride:methanol:ethyl acetate:triethylamine (4:4:5:0.1, by volume) and a reversed-phase (RP)-HPLC method where the chromatographic separation was performed using ethanol:water mixture (50: 50, v/v) as a mobile phase. Results: TLC-densitometric method had linearity over concentration ranges of 160-4000 ng/band for OLZ and 150-4500 ng/band for MET, while RP-HPLC method was linear and validated over concentration range of 300-20000 ng/ml for OLZ and MET. Conclusion: Pharmacokinetic study was successfully performed and suggested the possibility of co-administration of MET with OLZ and their further formulation in one pharmaceutical preparation to enhance patient's compliance.

Metformin for Weight Gain Associated with Second-Generation Antipsychotics in Children and Adolescents: A Systematic Review and Meta-Analysis

BACKGROUND

Weight gain is a potentially concerning side effect of second-generation antipsychotics (SGAs). Metformin, a biguanide with antihyperglycemic effects, is used to manage weight gain in adults treated with SGAs.

OBJECTIVE

The objective of this study was to perform the first systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of metformin on weight gain in children and adolescents treated with SGAs.

METHODS

Based on a pre-registered protocol (PROSPERO-CRD42017074839), we searched the PubMed, EMBASE, PsychoINFO, BIOSIS, Science Direct, Cochrane Central, and ClinicalTrials.gov electronic databases through March 2018 (with no restrictions on language, date, or type of publication) for RCTs that assessed the effect of metformin or placebo on body weight in children or adolescents (< 18 years of age) treated with selected SGAs (risperidone, aripiprazole, olanzapine, and clozapine) for any psychiatric disorder. We also contacted relevant drug manufacturers for possible additional pertinent studies/data. A random effects model was used and the quality of the included RCTs was assessed using the Cochrane Risk of Bias tool.

RESULTS

Five RCTs (205 participants in total) were included in the meta-analysis. We found a significant weight decrease in the metformin group compared with placebo after 4, 12, and 16 weeks of treatment {mean difference - 0.98 kg (95% confidence interval [CI] - 1.26, - 0.69); - 1.83 kg (95% CI - 2.47, - 1.18); and - 3.23 kg (95% CI - 5.59, - 0.86), respectively}. A weight decrease at weeks 2 and 8 did not reach statistical significance. The decrease in body mass index (BMI) paralleled that of weight, with a significant effect at weeks 4, 12, and 16. Overall, four studies were rated as unclear, and one study was rated as high, risk of bias.

CONCLUSION

Meta-analytical evidence shows that metformin might decrease weight in children/adolescents treated with SGAs but additional high-quality evidence is needed. Clinicians need to be aware that this use of metformin is currently off-label.

The effects of metformin on simple obesity: a meta-analysis

OBJECTIVE

To evaluate the efficacy of metformin versus a placebo in the treatment of patients with simple obesity without obesity related diseases.

METHODS

A search was done on Pub-Med, EMBASE, Cochrane, and Science Citation Index Expanded databases. The main inclusion criteria included the following:(1) randomized controlled trials. (2) patients diagnosed as being overweight or obese. (3) patients were randomly assigned to receive metformin or control. Exclusion criteria included the following: patients diagnosed with an obesity related disease, such as diabetes mellitus (DM) or polycystic ovary syndrome (PCOS).

RESULTS

Compared with the placebo, weighted mean difference (WMD) was 2.33 (95% CI 0.31, 4.35) kg higher with metformin (p = 0.02). Compared with the placebo, WMD was 0.57 (95% CI 0.35, 0.79) kg/m² higher with metformin(p < 0.00001). There was no significant difference in the reduction of waist circumference between the metformin group and the control group (p = 0.05). The fasting blood glucose levels were significantly lower in the metformin group than in the control group (p < 0.00001). However, no hypoglycemia was noted in the metformin group or the control group.

CONCLUSION

Metformin is effective in reducing body weight of simple obesity patients, and metformin does not induce hypoglycemia as a side effect.

Mechanisms in endocrinology: Antipsychotic medication and type 2 diabetes and impaired glucose regulation

OBJECTIVE

There have been concerns about the effects of antipsychotics on weight gain and the development of type 2 diabetes (T2DM). This article aims to provide an up-to-date review on the evidence addressing this issue and the practical implications for the management of people taking antipsychotics in the context of T2DM.

METHODS

We carried out searches on MEDLINE/PUBMED and the ClinicalTrials.gov website in August 2017 using the terms 'antipsychotic' and 'diabetes' or 'glucose' citing articles published after 2006 preferentially.

RESULTS

Antipsychotics are associated with T2DM and are likely to exert a causal effect of uncertain magnitude. Children and adolescents appear especially vulnerable to these metabolic effects; as T2DM is not common in healthy younger people, the relative risk is more apparent. Antipsychotics act on glucose and insulin homeostasis in a variety of direct and indirect mechanisms. To reduce the increasing health inequalities among individuals with mental illness screening, monitoring and prevention of T2DM is important, as is improved diabetes care in this population.

CONCLUSION

It remains unclear whether these antipsychotic medications exacerbate an underlying predisposition to the development of T2DM or have a direct effect. Potential risks need to be weighed up and balanced between improved and lasting mental health benefits and any detrimental physical health side effects. Achieving parity of esteem between mental and physical health is a worldwide priority if we wish to improve life expectancy and quality of life in people with severe mental illness.

The Wnt Signaling Pathway Effector TCF7L2 Mediates Olanzapine-Induced Weight Gain and Insulin Resistance

Olanzapine is a widely used atypical antipsychotic medication for treatment of schizophrenia and is often associated with serious metabolic abnormalities including weight gain and impaired glucose tolerance. These metabolic side effects are severe clinical problems but the underpinning mechanism remains poorly understood. Recently, growing evidence suggests that Wnt signaling pathway has a critical role in the pathogenesis of schizophrenia and molecular cascades of antipsychotics action, of which Wnt signaling pathway key effector TCF7L2 is strongly associated with glucose homeostasis. In this study, we aim to explore the characteristics of metabolic disturbance induced by olanzapine and to elucidate the role of TCF7L2 in this process. C57BL/6 mice were subject to olanzapine (4 mg/kg/day), or olanzapine plus metformin (150 mg/kg/day), or saline, respectively, for 8 weeks. Metabolic indices and TCF7L2 expression levels in liver, skeletal muscle, adipose, and pancreatic tissues were closely monitored. Olanzapine challenge induced remarkably increased body weight, fasting insulin, homeostasis model assessment-insulin resistance index, and TCF7L2 protein expression in liver, skeletal muscle, and adipose tissues. Notably, these effects could be effectively ameliorated by metformin. In addition, we found that olanzapine-induced body weight gain and insulin resistance actively influence the expression of TCF7L2 in liver and skeletal muscle, and elevated level of insulin determines the increased expression of TCF7L2 in adipose tissue. Our results demonstrate that TCF7L2 participates in olanzapine-induced metabolic disturbance, which presents a novel mechanism for olanzapine-induced metabolic disturbance and a potential therapeutic target to prevent the associated metabolic side effects.

Medication-induced diabetes mellitus

Epidemiological studies and case reports have demonstrated an increased rate of development of diabetes mellitus consequent to taking diverse types of medication. This review explores this evidence linking these medications and development of diabetes and presents postulated mechanisms by which the medications might cause diabetes. Some medications are associated with a reduction in insulin production, some with reduction in insulin sensitivity, and some appear to be associated with both reduction in insulin production and insulin sensitivity.

Metformin: an Old Therapy that Deserves a New Indication for the Treatment of Obesity

Metformin is not currently used for weight loss or diabetes prevention because it lacks an FDA indication for obesity and/or pre-diabetes treatment. Based on the evidence, metformin has been shown to decrease the incidence of type 2 diabetes, and compares favorably to other weight-loss medications in terms of efficacy as well as safety. Thus, metformin should be considered for a treatment indication in patients with these conditions.

Metformin for treatment of clozapine-induced weight gain in adult patients with schizophrenia: a meta-analysis

BACKGROUND

Long-term use of clozapine for individuals with schizophrenia carries a high risk for developing metabolic abnormalities, especially clozapine-induced weight gain. Previous studies suggest that metformin can decrease clozapine-induced weight gain, but the sample sizes of most of these studies are relatively small.

METHODS

We identified randomized controlled trials (RCTs) published prior to December 15, 2015 about the use of metformin to treat clozapine-induced weight gain in adults with schizophrenia by searching several English-language and Chinese-language databases. Two independent researchers did the screening and data extraction. We used Revman 5.3 to conduct the meta-analyses, assessed the risk of bias (RoB), and assessed the strength of the evidence using the Cochrane Grades of Recommendation, Assessment, Development, and Evaluation (GRADE).

RESULTS

Six studies with a pooled sample of 207 treatment-group patients and 207 control-group patients were included -- three double-blind, placebo-controlled RCTs and three RCTs that did not use placebo controls and were not blinded. The meta-analysis found that compared to the control condition, patients receiving metformin experienced significantly greater reductions in body weight (mean difference [MD]=-2.89 kg, 95% CI: -4.20 to -1.59 kg) and body mass index (BMI) (MD=-0.81, 95% CI: -1.16 to -0.45), but there was no significant difference between the groups in the prevalence of side effects. Based on the GRADE scale, the strength of the evidence for the change in weight outcome was 'moderate' and that for the change in BMI outcome was 'high', but the strength of evidence about differences in side effects between groups was 'low' or 'very low'.

CONCLUSIONS

Adjunctive treatment with metformin appears to be effective for treating clozapine-induced weight gain and elevations in BMI in adult patients with schizophrenia. However, the quality of the evidence about the safety of this treatment is low, follow-up time in the available studies is relatively short, and half of the studies did not employ blinded assessment of outcome measures. Larger studies with placebo controls that follow patients for at least 24 weeks and that make blinded assessments of a range of relevant outcome measures (weight, BMI, blood lipids, insulin resistance, etc.) are needed to confirm these results.

Metformin for Weight Gain and Metabolic Abnormalities Associated With Antipsychotic Treatment: Meta-Analysis of Randomized Placebo-Controlled Trials

This meta-analysis examined the effectiveness and safety of metformin to prevent or treat weight gain and metabolic abnormalities associated with antipsychotic drugs. We systematically searched in both English- and Chinese-language databases for metformin randomized controlled clinical trials (RCTs) using placebo in patients taking antipsychotics. Twenty-one RCTs (11 published in English and 10 in Chinese) involving 1547 subjects (778 on metformin, 769 on placebo) were included in this meta-analysis. Metformin was significantly superior to placebo (standard mean differences, -0.69 to -0.51; P = 0.01-0.0001) in the primary outcome measures (body weight, body mass index, fasting glucose, fasting insulin, triglycerides, and total cholesterol). Metformin was significantly superior to placebo in some secondary outcome measures but not in others. Significantly higher frequencies of nausea/vomiting and diarrhea were found in the metformin group, but no differences were found in other adverse drug reactions. In the metformin group, the frequency of nausea/vomiting was 14%, and of diarrhea, 7%. Subgroup and sensitivity analyses demonstrated that primary outcomes were influenced by ethnicity, treatment style (intervention vs prevention), metformin dose, study duration, and mean age. Body weight standard mean difference was -0.91 (confidence interval [CI], -1.40 to -0.41) in 3 prevention RCTs in naive patients, -0.66 (CI, -1.02 to -0.30) in 5 intervention RCTs during the first year, and -0.50 (CI, -0.73 to -0.27) in 9 intervention RCTs in chronic patients. This meta-analysis suggests that adjunctive metformin is an effective, safe, and reasonable choice for antipsychotic-induced weight gain and metabolic abnormalities.

Antipsychotics inhibit glucose transport: Determination of olanzapine binding site in Staphylococcus epidermidis glucose/H(+) symporter

The antipsychotic drug olanzapine is widely prescribed to treat schizophrenia and other psychotic disorders. However, it often causes unwanted side effects, including diabetes, due to disruption of insulin-dependant glucose metabolism through a mechanism yet to be elucidated. To determine if olanzapine can affect the first step in glucose metabolism - glucose transport inside cells - we investigated the effect of this drug on the transport activity of a model glucose transporter. The glucose transporter from Staphylococcus epidermidis (GlcPSe) is specific for glucose, inhibited by various human glucose transporter (GLUT) inhibitors, has high sequence and structure homology to GLUTs, and is readily amenable to transport assay, mutagenesis, and computational modeling. We found that olanzapine inhibits glucose transport of GlcPSe with an IC50 0.9 ± 0.1 mM. Computational docking of olanzapine to the GlcPSe structure revealed potential binding sites that were further examined through mutagenesis and transport assay to identify residues important for olanzapine inhibition. These investigations suggest that olanzapine binds in a polar region of the cytosolic part of the transporter, and interacts with residues R129, strictly conserved in all GLUTs, and N136, conserved in only a few GLUTs, including the insulin-responsive GLUT4. We propose that olanzapine inhibits GlcPSe by impeding the alternating opening and closing of the substrate cavity necessary for glucose transport. It accomplishes this by disrupting a key salt bridge formed by conserved residues R129 and E362, that stabilizes the outward-facing conformation of the transporter.

Strategies for prevention and management of second generation antipsychotic-induced metabolic side effects

Preventing, minimizing and managing risks associated with second generation antipsychotic (SGA) use in patients with schizophrenia and other psychotic disorders is a priority for clinicians working with this population. Among these risks is metabolic syndrome. As this population exhibits increased rates of obesity, diabetes and atherogenic dyslipidemia compared to the general population, metabolic syndrome deserves serious consideration in patient care planning for managing risks. This article comprehensively reviews different strategies and recommendations for prevention and/or management of metabolic abnormalities associated with the use of SGAs. Baseline screening and follow-up metabolic monitoring as well as education and counseling on risk for SGA-induced weight gain and other metabolic abnormalities, physical activity and healthy diet for weight maintenance/loss should be promoted shortly after initiation of SGAs. In select patients, the clinician can consider simplifying the antipsychotic treatment regimen by switching to an agent with a lower propensity of metabolic side effects or possibly adding metformin for weight loss and glucose metabolism regulation in those experiencing a first episode of schizophrenia. Future research should focus on combinations of interventions and treatment modalities and exploration of novel interventions.

The relationship between bipolar disorder and type 2 diabetes: more than just co-morbid disorders

Type 2 diabetes mellitus (T2DM) rates are three times higher in patients with bipolar disorder (BD), compared to the general population. This is a major contributing factor to the elevated risk of cardiovascular mortality, the leading cause of death in bipolar patients. There may be shared pathophysiology linking the two disorders, including hypothalamic-pituitary-adrenal and mitochondrial dysfunction, common genetic links, and epigenetic interactions. Life-style, phenomenology of bipolar symptoms, and adverse effects of pharmacotherapy may be contributing factors. Patients with BD and T2DM have a more severe course of illness and are more refractory to treatment. Control of their diabetes is poorer when compared to diabetics without BD, and an existing disparity in medical care may be partly responsible. Glucose abnormalities in bipolar patients need to be screened for and treated. Metformin appears to have the best benefit/risk ratio, and the dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists and analogues also appear promising, although these agents have not been specifically studied in populations with mood disorders. Physicians need to be aware of the increased risk for T2DM and cardiovascular disease in bipolar patients, and appropriate prevention, screening, case finding, and treatment is recommended.

Weight gain and glucose dysregulation with second-generation antipsychotics and antidepressants: a review for primary care physicians

Second-generation antipsychotics (SGAPs) and second-generation antidepressants (SGADs) have multiple US Food and Drug Administration-approved indications and are frequently prescribed by primary care physicians. We review the relative potential of these drugs to cause weight gain and glucose dysregulation, and offer clinical guidance to minimize and manage this risk. Among SGAPs, clozapine and olanzapine have a high risk for causing weight gain and glucose dysregulation; iloperidone, paliperidone, quetiapine, and risperidone have a medium risk; and aripiprazole, asenapine, lurasidone, and ziprasidone have a low risk. Young, drug-naïve patients are particularly vulnerable to weight gain associated with SGAPs. With the exception of clozapine, SGAPs have modest differences in their efficacy; however, their side effect profiles may influence selection. Using SGAPs with high metabolic liability conservatively and limiting their off-label use are important means to minimize risk. Patients should be screened before initiating any SGAP (or any antipsychotic medication) and monitored subsequently following standard guidelines, such as those provided by the American Diabetes Association. Healthy lifestyle counseling should be offered to all patients. Patients showing evidence of significant weight gain should be switched to an SGAP with a lower metabolic liability. Metformin may have some utility in young patients with limited exposure to antipsychotic drugs if lifestyle interventions fail and switching the SGAP is not an option. This option should be tried sooner than later for the best possible result. For SGADs, paroxetine and mirtazapine are associated with weight gain, and bupropion may cause modest weight loss. Other SGADs are mostly weight neutral, but individual variations may occur. Depression is associated with weight change and is a risk factor for glucose dysregulation. Treatment of depression improves glucose metabolism. We recommend that all patients taking SGADs be screened using anthropometric measures and metabolic assessment at baseline. Monitoring should be guided individually based on weight gain and other risk factors.

Amantadine for olanzapine-induced weight gain: a systematic review and meta-analysis of randomized placebo-controlled trials

OBJECTIVE

The objective of this study was to conduct a systematic review and meta-analysis of randomized placebo-controlled trials of amantadine for the treatment of olanzapine-induced weight gain.

METHODS

Studies were identified using online searches of PUBMED/MEDLINE and Cochrane database (CENTRAL), along with websites recording trial information such as ClinicalTrials.gov, Controlled-trials.com, and Clinicalstudyresults.org. Study eligibility criteria included randomized, double-blind clinical trials comparing amantadine with placebo for olanzapine-induced weight gain with body weight as an outcome measure and study duration of at least 12 weeks. The methodological quality of included trials was assessed using the Jadad Scale. Separate meta-analyses were undertaken for each outcome (body weight and frequency of weight loss >7%) and treatment effects were expressed as weighted mean differences (WMD) and Mantel-Haenszel odds ratio for continuous and categorical outcomes, respectively.

RESULTS

A systematic review of literature revealed six studies that had assessed amantadine for olanzapine-induced weight gain. Of these, two studies (n = 144) met the review inclusion criteria and were included in the final analysis. Meta-analysis was performed to see the effect size of the treatment on body weight and frequency of body weight loss >7%. For body weight change, WMD was -1.85 (95% confidence interval [CI] -3.31 to -0.39) kg with amantadine as compared with placebo; the overall effect was statistically significant (p = 0.01). For frequency of body weight loss >7%, Mantel-Haenszel odds ratio for weight loss was 3.72 (95% CI 1.19-11.62), favoring amantadine as compared with placebo, and the overall effect was significant (p = 0.02).

CONCLUSIONS

Existing data is limited to two studies, which support the efficacy of amantadine for olanzapine-induced weight gain and a significant proportion of patients might lose weight with amantadine compared with placebo.

Metformin for obesity and glucose dysregulation in patients with schizophrenia receiving antipsychotic drugs

Antipsychotic drug-induced weight gain and glucose dysregulation add to the cardiovascular risk of patients with schizophrenia and contribute to their early mortality. The currently recommended interventions to address the metabolic complications of antipsychotic drug treatment are to switch the patient from an antipsychotic drug with high metabolic liability to one with a lower liability and to implement lifestyle changes. These interventions can be quite challenging to carry out. So far the progress in improving the metabolic and cardiovascular outcome of patients with major mental illness has been disappointing. We offer an overview of the literature on metformin for antipsychotic drug-induced weight gain and glucose dysregulation and pertinent literature from the Diabetes Prevention Program. We conclude that young adults with schizophrenia newly exposed to antipsychotic drugs, who show a pattern of rapid weight gain and/or glucose dysregulation, are prime candidates for metformin if switching the antipsychotic medication to one with a lower metabolic burden is not an option or does not curtail the weight gain and/or adverse metabolic effects. Metformin therapy should not preclude healthy lifestyle interventions.

Metformin for olanzapine-induced weight gain: a systematic review and meta-analysis

Olanzapine is an atypical antipsychotic that is useful in schizophrenia and bipolar affective disorder, but its use is associated with troublesome weight gain and metabolic syndrome. A variety of pharmacological agents has been studied in the efforts to reverse weight gain induced by olanzapine, but current evidence is insufficient to support any particular pharmacological approach. We conducted a systematic review and meta-analysis of randomized controlled trials of metformin for the treatment of olanzapine-induced weight gain. Systematic review of the literature revealed 12 studies that had assessed metformin for antipsychotic-induced weight gain. Of these, four studies (n= 105) met the review inclusion criteria and were included in the final analysis. Meta-analysis was performed to see the effect size of the treatment on body weight, waist circumference and body-mass index (BMI). Weighted mean difference (WMD) for body weight was 5.02 (95% CI 3.93, 6.10) kg lower with metformin as compared with placebo at 12 weeks. For waist circumference, the test for heterogeneity was significant (P= 0.00002, I(2) = 85.1%). Therefore, a random effects model was used to calculate WMD, which was 1.42 (95% CI 0.29, 3.13) cm lower with metformin as compared with placebo at 12 weeks. For BMI, WMD was 1.82 (95% CI 1.44, 2.19) kg m(-2) lower with metformin as compared with placebo at 12 weeks. Existing data suggest that short term modest weight loss is possible with metformin in patients with olanzapine-induced weight gain.

Cardiovascular aspects of antipsychotics

PURPOSE OF REVIEW

Schizophrenia is associated with increased mortality and reduced life expectancy, with cardiovascular disease being the most frequent cause of death. Antipsychotics have detrimental effects on different risk factors for cardiovascular disease. This review will focus on the relationship between antipsychotic treatment and cardiovascular disease.

RECENT FINDINGS

The increased overall mortality and mortality from cardiovascular disease in schizophrenia are now well documented. Patients with schizophrenia are at risk of receiving less optimal treatment for cardiovascular disease. Patients with schizophrenia are at high risk of metabolic syndrome, a cluster of risk factors for cardiovascular disease. Some antipsychotics, in particular, clozapine and olanzapine, frequently cause weight gain, dyslipidemia and diabetes mellitus. Antipsychotics differ in their effects on body weight, lipids and glucose regulation. However, the long-term effects of these differences between individual antipsychotics on overall mortality and cardiovascular mortality are not well established.

SUMMARY

More research is needed to better understand the relationship between schizophrenia, antipsychotic treatment and cardiovascular disease. More effective treatment strategies need to be developed to reduce the burden of cardiovascular disease in schizophrenia.

Metabolic syndrome with the atypical antipsychotics

PURPOSE OF REVIEW

Metabolic syndrome and cardiovascular diseases are important causes of morbidity and mortality among patients with severe mental illnesses. Atypical or second-generation antipsychotics (SGAs) are associated with obesity and other components of metabolic syndrome, particularly abnormal glucose and lipid metabolism. This review aims to provide a summary of recent evidence on metabolic risks associated with SGAs, current recommendations for metabolic monitoring, and efficacy of treatment options currently available.

RECENT FINDINGS

Studies have identified younger, antipsychotic-naive patients with first-episode psychosis as a population vulnerable to adverse metabolic effects from SGAs. These patients gained more weight and developed evident lipid and glucose abnormalities as soon as 8-12 weeks after treatment initiation. Findings are more striking among children and adolescents. The differential effects of various SGAs are well described, with clozapine and olanzapine associated with the highest metabolic risk. In addition to behavioral therapy, emerging data suggest that pharmacological therapy, most notably metformin, is efficacious in the treatment and possibly prevention of SGA-associated metabolic derangements.

SUMMARY

More data have become available on the burden from metabolic complications associated with SGAs. New and effective treatment options are required in the near future to improve cardiovascular health in this susceptible population.

Metabolic syndrome associated with schizophrenia and atypical antipsychotics

Patients with schizophrenia are at increased risk for developing the metabolic syndrome or its individual components due to their lifestyle, suspected genetic predisposition, and exposure to antipsychotic medications that can cause weight gain and other metabolic side effects. Despite the availability of clinical guidelines, screening for and monitoring of metabolic problems in this patient population continue to be suboptimal. We provide an overview specifically addressing 1) why patients with schizophrenia are at increased risk for metabolic problems; 2) how commonly used antipsychotic medications vary in terms of their metabolic liability; 3) how to effectively screen for and monitor metabolic problems in patients receiving antipsychotic medications; 4) what interventions can prevent, limit, or reverse the metabolic side effects of antipsychotic drug treatment; and 5) what are the barriers to the care of these patients.