Does Propranolol Cause Weight Gain?
Yes, propranolol causes modest but sustained weight gain, with patients gaining approximately 1-2 kg more than those not taking the medication over 6-24 months of treatment. 1, 2
Evidence for Weight Gain
Magnitude and Timeline of Weight Gain
At 6 months: Propranolol causes approximately 1.0 kg more weight gain compared to lisinopril (a weight-neutral comparator), with patients on propranolol gaining weight while lisinopril users actually lose weight. 1
At 12 months: The weight difference persists at approximately 1.7 kg compared to lisinopril, demonstrating that this is not a transient effect. 1
Long-term data: In post-myocardial infarction patients followed for up to 40 months, propranolol users gained 2.3 kg versus 1.2 kg in placebo-treated patients (mean difference of 1.2 kg), and this difference remained sustained at annual follow-up visits. 2
Mechanism of Weight Gain
Metabolic rate reduction: Beta-blockers decrease metabolic rate by approximately 10%, which directly contributes to weight accumulation over time. 3
Energy metabolism effects: Beyond reducing metabolic rate, beta-blockers may have additional negative effects on energy metabolism that make weight management more difficult. 3
Not explained by confounders: The weight gain occurs independent of diuretic use, physical activity levels, sex, or age, indicating it is a direct pharmacologic effect. 2
Clinical Context and Comparison to Other Medications
Propranolol Among Beta-Blockers
Propranolol is consistently associated with weight gain across multiple studies, similar to metoprolol (another non-selective beta-blocker). 1
Other beta-blockers like atenolol show less consistent weight gain effects, though the beta-blocker class overall is recognized as weight-promoting. 4, 5
Propranolol Among Migraine Preventives
- When used for migraine prophylaxis, propranolol causes less weight gain than amitriptyline or divalproex sodium, but more than timolol (which is weight-neutral) or topiramate (which causes weight loss). 6
Clinical Implications
Patient Selection Considerations
Avoid propranolol as first-line therapy in overweight or obese hypertensive patients without compelling cardiovascular indications, as the weight gain may worsen obesity-related comorbidities and make weight management more difficult. 3
For migraine prevention in weight-conscious patients, consider topiramate (associated with weight loss) or timolol (weight-neutral) instead of propranolol. 6
When Propranolol Is Necessary
Monitor weight regularly (at least every 3-6 months) when propranolol is prescribed long-term. 2
Counsel patients proactively about expected weight gain of 1-2 kg to set realistic expectations and encourage dietary/exercise modifications at treatment initiation. 1, 2
Consider that the weight gain is sustained rather than progressive—patients typically gain 1-2 kg in the first 6-12 months, which then plateaus. 1, 2
Important Caveats
The weight gain with propranolol is modest (1-2 kg) compared to medications like mirtazapine, amitriptyline, or atypical antipsychotics, which cause substantially greater weight increases. 4, 5
Despite the weight gain, propranolol remains appropriate when there are compelling cardiovascular indications (post-MI, heart failure, certain arrhythmias), as the mortality benefit outweighs the metabolic concerns. 2
The association between beta-blockers and weight gain appears underrecognized, as only a minority of clinical trials report weight changes during beta-blocker treatment. 3