Is the Lexapro (escitalopram) or the Nexplanon (etonogestrel implant) causing weight gain?

Weight Gain: Nexplanon vs. Lexapro

Both Nexplanon (etonogestrel implant) and Lexapro (escitalopram) can contribute to weight gain, but Lexapro is more likely to be the primary cause of your weight gain.

Lexapro (Escitalopram) and Weight Gain

Escitalopram belongs to the selective serotonin reuptake inhibitor (SSRI) class of antidepressants, which have varying effects on weight:

• According to clinical guidelines, within the SSRI class, escitalopram (Lexapro) has a moderate risk of weight gain 1
• The FDA label for escitalopram does not specifically list weight gain as a common side effect, but does mention "increased appetite" as a possible adverse reaction 2
• Recent research shows that escitalopram is associated with higher weight gain compared to several other antidepressants, with an estimated 6-month weight gain difference of 0.41 kg more than sertraline 3

While some SSRIs like fluoxetine and sertraline may cause weight loss with short-term use and weight neutrality with long-term use, escitalopram tends to cause more weight gain over time 1.

Nexplanon (Etonogestrel) and Weight Gain

Progestin-only contraceptives like Nexplanon have variable effects on weight:

• The FDA label for etonogestrel implant does not specifically list weight gain as a common adverse reaction 4
• A Cochrane review mentioned in guidelines indicates that medroxyprogesterone acetate (a different progestin) is associated with weight gain, but there is less clear evidence regarding etonogestrel implants 1
• Hormonal contraceptives have variable weight effects depending on their formulation, with some being more weight-neutral than others 1

Comparative Analysis

When comparing the two medications:

1. Escitalopram (Lexapro):

   • Has more consistent evidence of causing weight gain in clinical studies
   • Recent large-scale research shows it causes more weight gain than several other antidepressants 3
   • Weight gain with SSRIs tends to be progressive over time

2. Etonogestrel (Nexplanon):

   • Has less consistent evidence linking it to significant weight gain
   • Individual responses to hormonal contraceptives vary considerably
   • Some hormonal contraceptives are relatively weight-neutral

Management Options

If weight gain is concerning:

1. For depression treatment alternatives:

   • Bupropion is the only antidepressant consistently shown to promote weight loss 1, 3
   • Fluoxetine may be more weight-neutral compared to escitalopram 3
   • Any medication switch should be done under medical supervision to maintain depression control

2. For contraception alternatives:

   • Weight-neutral contraceptive options include barrier methods and copper intrauterine devices 1
   • Individual responses to hormonal methods vary significantly

Important Considerations

• Weight changes on medications are often multifactorial
• Never discontinue either medication abruptly without medical supervision
• The primary goal should be maintaining both effective depression treatment and contraception
• Weight management strategies including diet and exercise remain important regardless of medication choice

If weight gain is significantly impacting your quality of life, discuss with your healthcare provider about potentially switching your antidepressant to bupropion, which is the only antidepressant consistently associated with weight loss rather than weight gain.