Austin and Jordan,
I hear many folks in the clinic speak of difficulty losing weight and blaming the use of anti-depressants. I hear physicians say the same to their patients.
My question is by what mechanism would weight gain be a side effect? Behavioral? Metabolic? Combination? Has the evidence been able to suggest a primary mechanism?
Thanks so much!
Matt
Weight changes in the context of depression therapy are a bit complex. For example (from Weight gain and antidepressants - PubMed ):
“Weight gain during antidepressant treatment can be either a sign of improvement in patients who have weight loss as a symptom of depression or a residual symptom in patients who overeat when depressed. However, significant weight gain during the acute phase of treatment or weight gain that continues despite achieving full remission of depressive symptoms is likely to be a side effect of antidepressant treatment.”
Antidepressants and antipsychotics (the latter are often used as adjunctive therapy in depression) act on a variety of neurotransmitter pathways and receptors to varying degrees, including serotonergic, dopaminergic, adrenergic, cholinergic, and histaminergic. To get an idea of how complex this is, check out the pharmacodynamics for any of these medications, such as paroxetine: https://en.wikipedia.org/wiki/Paroxe…armacodynamics . Certain antipsychotics (like clozapine and olanzapine) can cause fairly severe cardiometabolic derangements stemming from insulin resistance as well.
Because of variability between medication binding profiles, we see slightly different risks with respect to weight gain as a side effect. Here’s a good resource I use to discuss this topic when selecting options with patients: https://cdn.prod-carehubs.net/n1/56f…ight_WEB-1.pdf . The Mayo Clinic Decision Aids are quite good for this sort of thing – here’s the aid for antidepressants: Mayo Clinic (and, as an aside they have one for statins as well: http://statindecisionaid.mayoclinic.org )