Non-endocrine involuntary weight gain

Specialty: General.

• unexplained weight gain
• weight gain not related to diet
• involuntary accumulation of body mass

Why it occurs

• Massive fluid retention due to heart, kidney or liver failure (where the decrease in effective arterial volume activates the renin-angiotensin-aldosterone system causing accumulation of water and sodium)
• Adverse effect of non-hormonal medications (tricyclic antidepressants, atypical antipsychotics such as olanzapine, or antiepileptics such as sodium valproate, which alter the hypothalamic satiety center)
• Drastic decrease in energy expenditure due to forced immobilization or severe physical deconditioning after complex pathological processes
• Hidden eating disorders (night eating syndrome or unreported binge eating episodes)
• Giant intra-abdominal or retroperitoneal neoplastic expansive processes (giant ovarian cysts, myxomas or retroperitoneal sarcomas that simulate fatty weight gain).

Initial workup

24-hour urine analysis for protein quantification and creatinine clearance, transthoracic echocardiogram, complete abdominal ultrasound with portal Doppler, metabolic profile that includes lipid profile, and exhaustive review of the list of active drugs.

Standard management

• Furosemide — 20 to 40 mg orally once a day in the morning, only if it is confirmed that the weight gain is due to water overload due to organ failure
• Spironolactone — 25 to 100 mg per day if the origin of the retention is linked to liver cirrhosis with ascites, under strict potassium control
• Directed suspension or dose adjustment of weight-inducing drugs under the advice of the corresponding specialist.