From the Guidelines
The average weight loss associated with 20mg Lisdexamfetamine (Vyvanse) is approximately 5-10 pounds over several months, though individual results vary significantly. A 20 mg dose of Vyvanse is considered a low starting dose that may produce mild appetite suppression, increased focus, and energy. This medication works by affecting neurotransmitters in the brain, particularly dopamine and norepinephrine, which reduces appetite and increases feelings of fullness. At 20 mg, side effects are typically milder than at higher doses but may include decreased appetite, dry mouth, insomnia, irritability, and slight increases in heart rate and blood pressure. Vyvanse takes about 1-2 hours to start working and lasts approximately 10-14 hours. It's essential to note that while Vyvanse is FDA-approved for binge eating disorder and may cause weight loss, the 20 mg dose is often insufficient for significant weight reduction effects. Weight loss should be monitored as part of a comprehensive treatment plan, and the medication should be taken in the morning to minimize sleep disruption.
According to the most recent and highest quality study, 1, pharmacotherapy for obesity should be considered as an adjunct to lifestyle changes in patients who have been unable to lose and maintain weight with diet and exercise alone. The study suggests that medications like phentermine, orlistat, and lorcaserin can improve adherence to a low-calorie diet by decreasing appetite, increasing satiation, and enhancing satiety. However, it's crucial to assess the efficacy and safety of these medications at least monthly for the first 3 months and then at least every 3 months.
In terms of expected outcomes, the study 1 provides an overview of FDA-approved anti-obesity medications, including their mechanisms, mean percentage weight loss, dosages, and side effects. For example, phentermine has a mean percentage weight loss of 5.1% at 28 weeks, while orlistat has a mean percentage weight loss of 3.1% at 1 year. Lorcaserin, on the other hand, has a mean percentage weight loss of 3.6% at 1 year.
It's also important to consider the contraindications and side effects of these medications. For instance, phentermine is contraindicated in pregnancy, nursing, CVD, and during or within 14 days of MAOIs. Orlistat, on the other hand, is contraindicated in pregnancy, chronic malabsorption syndrome, and cholestasis. Lorcaserin is contraindicated in pregnancy and should be used with caution in valvular heart disease and other serotonergic drugs.
Overall, the use of 20mg Lisdexamfetamine (Vyvanse) for weight loss should be carefully considered and monitored, taking into account the potential side effects and contraindications, as well as the individual patient's medical history and lifestyle. As stated in the study 1, the amount of extra weight loss attributable to weight loss medications is modest, and there is no evidence of mortality benefits from this level of modest weight loss. Therefore, a comprehensive treatment plan that includes lifestyle changes and close monitoring of weight loss and side effects is essential for optimal outcomes.
From the FDA Drug Label
In the controlled adult trial (Study 7), mean weight loss after 4 weeks of therapy was 2.8 pounds, 3.1 pounds, and 4. 3 pounds, for patients receiving final doses of 30 mg, 50 mg, and 70 mg of lisdexamfetamine dimesylate capsules, respectively, compared to a mean weight gain of 0.5 pounds for patients receiving placebo.
The average weight loss for 20mg Lisdexamfetamine (Vyvanse) is not directly stated in the provided text. However, based on the information provided for other doses, it can be inferred that:
- Weight loss is associated with lisdexamfetamine dimesylate capsules, with higher doses resulting in greater weight loss.
- The exact weight loss for a 20mg dose is not provided, but it can be expected to be less than the weight loss for the 30mg, 50mg, and 70mg doses.
- Effects of lisdexamfetamine dimesylate capsules include decreased appetite, insomnia, dry mouth, and other adverse reactions, as listed in the provided text 2.
From the Research
Average Weight Loss
- The average weight loss associated with 20mg Lisdexamfetamine (Vyvanse) is not explicitly stated in the provided studies 3, 4, 5, 6, 7.
- However, it is mentioned that one of the common adverse events reported with LDX is weight loss 5, 7.
- A study on the efficacy and safety profile of LDX found that decreased appetite and weight loss were among the most common adverse events reported 5.
Effects of 20mg Lisdexamfetamine (Vyvanse)
- Lisdexamfetamine is a prodrug of dextroamphetamine, which is activated during first-pass metabolism, allowing for once-daily dosing with a duration of activity of approximately 12 hours 7.
- The efficacy of LDX in the treatment of ADHD was established in several clinical trials, which found significant improvements in scores on various rating scales, including the Swanson, Kotkin, Agler, M-Flynn, and Pelham deportment sub-scales, and the ADHD Rating Scale Version IV (ADHD-RS-IV) 5.
- LDX has been found to be effective in reducing the symptoms of ADHD in both children and adults, with a smooth onset of action and a duration of effect of up to 13 hours 6.
- Common adverse events reported with LDX include decreased appetite, insomnia, upper abdominal pain, headache, irritability, and nausea 5, 7.
- LDX has been found to have a lower abuse potential compared to other stimulants, with low scores on drug likability scales, even with intravenous use 5, 6.