Currently, we are unable to predict which weight loss
medication will result in the greatest weight loss for a given
individual. If one medication is poorly tolerated or ineffective,
another should be trialed. When indicated, obesity medications
can be used simultaneously if the expected clinical outcome is
to further reduce daily caloric consumption—however, both an
increased risk for adverse effects as well as cost-effectiveness
must be considered.
We suggest patient assessment monthly for the first 3 months
of medication use, and every 3 months thereafter.
initiated on liraglutide should be monitored for gastrointestinal
side effects and injection site reactions. Patients started on NB
should be monitored for gastrointestinal side effects, worsening
hypertension, tachycardia, anxiety, suicidal ideation, and
worsening headaches. Recommended baseline and follow-up
investigations are the same as for patients undergoing an isolated
After 12 weeks at the target dose, an
anti-obesity medication should be discontinued if 5% weight loss
has not been achieved. Cross-over trials of obesity medications
consistently show accelerated weight regain when medication is
As such, anti-obesity medications, as medications
for any other chronic disease (e.g., hypertension, type 2 diabetes,
etc.), should be continued indefinitely when they are effective
Obesity treatment has historically been a frustrating aspect of
medical practice for primary care practitioners; the long-term
outcomes of behavioral therapy are disappointing, bariatric
surgery is scarcely available, and medications have been
poorly effective. The newest anti-obesity medications target
the neurohormonal regulation of appetite, addressing a key
mechanism in the pathophysiology of obesity. These medications
allow physicians to deliver more effective obesity therapy to a
greater number of patients.
Conflicts of Interest
Authors R.M., S.C., and A.S. have received speaker and consulting
honorarium from Novo Nordisk and Bausch Health. Authors
R.K and J.D have no conflict of interest to disclose.
1. Statistics Canada. Canadian community health survey. Body mass index,
overweight or obese, self-reported, adult, age groups (18 years and older).
2017 [cited 2018 Sept 04].
2. cma.ca [Internet]. Canada: CMA recognizes obesity as a disease; c2018 [cited
2018 Jul 25]. Available from: https://www.cma.ca/En/Pages/cma-recognizes-
3. Katzmarzyk PT, Ardern CI. Overweight and obesity mortality trends in
Canada, 1985–2000. Can J Public Health. 2004;95(1):16–20. http://dx.doi.
4. Puhl RM, Suh Y. Health consequences of weight stigma: Implications for
obesity prevention and treatment. Curr Obes Rep. 2015;4(2):182–90. http://
5. Kahan S, Puhl RM. The damaging effects of weight bias internalization.
Obesity. 2017;25(2):280–1. http://dx.doi.org/10.1002/oby.21772
6. Lau D, Douketis J, Morrison K, Hramiak I, Sharma A, Ur E. 2006 Canadian
clinical practice guidelines on the management and prevention of obesity
in adults and children [summary]. CMAJ. 2007;176(8):S1–13. http://dx.doi.
7. obesitycanada.ca [Internet]. Canada: Report card on access to
obesity treatment for adults in Canada; c2018 [cited 2018 Jun
26]. Available from: https://obesitycanada.ca/publications/
8. James WP, Caterson ID, Coutinho W, Finer N, Van Gaal LF, Maggioni AP,
et al. Effect of sibutramine on cardiovascular outcomes in overweight and
obese subjects. NEJM. 2010;363(10):905–17. http://dx.doi.org/10.1056/
9. Davidson M, Hauptman, J, DiGirolamo, M, Foreyt, J, Halsted, C, Heber, D,
et al. Weight control and risk factor reduction in obese subjects treated for 2
years with orlistat: A randomized controlled trial. JAMA. 1999;281:235–42.
10. Wharton S. Current perspectives on long-term obesity pharmacotherapy.
Can J Diabetes. 2016;40(2):184–91. http://dx.doi.org/10.1016/j.
11. Naltrexone. Product monograph. Toronto, ON: Teva Canada Limited; 2015.
12. Bupropion Hydrochloride (Wellbutrin). Product monograph. Laval, QC:
Valeant Canada LP; 2017.
13. Bupropion Hydrochloride (Zyban). Product monograph. Laval, QC: Valeant
Canada LP; 2016.
14. Marso SP, Daniels GH, Brown-Frandsen K, Kristensen P, Mann JF, Nauck
MA, et al. Liraglutide and cardiovascular outcomes in type 2 diabetes. NEJM.
15. Nissen SE, Wolski KE, Prcela L, Wadden T, Buse JB, Bakris G, et al. Effect
of naltrexone-bupropion on major adverse cardiovascular events in
overweight and obese patients with cardiovascular risk factors: A randomized
clinical trial. JAMA. 2016;315(10):990–1004. http://dx.doi.org/10.1001/
16. Volkow ND, Wang GJ, Tomasi D, Baler RD. Obesity and addiction:
Neurobiological overlaps. Obes Rev. 2013;14(1):2–18. http://dx.doi.
17. Volkow ND, Wang GJ, Baler RD. Reward, dopamine and the control of food
intake: Implications for obesity. Trends Cogn Sci. 2011;15(1):37–46. http://
18. Saxenda. Product monograph. Mississauga, ON: Novo Nordisk Canada Inc.;
19. Contrave. Product monograph. Laval, QC: Valeant Canada LP; 2018.
20. Wadden TA, Hollander P, Klein S, Niswender K, Woo V, Hale PM, et al.
Weight maintenance and additional weight loss with liraglutide after low-
calorie-diet-induced weight loss: The SCALE maintenance randomized
study. Int J Obes (Lond). 2013;37(11):1443–51. http://dx.doi.org/10.1038/
21. le Roux CW, Astrup A, Fujioka K, Greenway F, Lau DC, Van Gaal L, et al.
3 years of liraglutide versus placebo for type 2 diabetes risk reduction and
weight management in individuals with prediabetes: A randomised, double-
blind trial. Lancet. 2017;389(10077):1399–409. http://dx.doi.org/10.1016/
22. Davies MJ, Bergenstal R, Bode B, Kushner RF, Lewin A, Skjoth TV, et al.
Efficacy of liraglutide for weight loss among patients with type 2 diabetes:
The SCALE diabetes randomized clinical trial. JAMA. 2015;314(7):687–99.
23. Blackman A, Foster GD, Zammit G, Rosenberg R, Aronne L, Wadden T, et al.
Effect of liraglutide 3.0 mg in individuals with obesity and moderate or severe
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