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Xenical (orlistat) and Alli

Xenical (orlistat) and Alli: Xenical (prescription) and Alli (over-the-counter) are FDA-approved weight loss medications that work by inhibiting the absorption of dietary fat. Side effects include oily stools, gas, and abdominal pain. Alli and Xenical are available in the US.

Xenical contains orlistat, the same fat blocker found in Alli.
Era of Discovery

1999 and 2007

Mechanism of Action

Inhibit absorption of dietary fat

History of Use in the United States

Approved in 1999 (Xenical) and 2007 (Alli)

Benefit of Weight Loss Agent or Medication

Weight loss due to reduced fat absorption

Possible Side Effects

Oily stools, gas, abdominal pain

Current Regulatory Status in US

Available in the US (Xenical by prescription, Alli OTC)

Xenical and Alli: A Non-Stimulant Approach to Weight Loss

The history of weight loss drugs has been marked by a steady search for safe and effective treatments. The launch of orlistat, marketed as Xenical and Alli, represented a significant departure from the stimulant-based drugs of the past, offering a novel, non-stimulant approach to weight management.

The Birth of Orlistat: A Novel Approach to Weight Loss

Orlistat, a lipase inhibitor, was developed by Swiss multinational healthcare company Roche. Approved by the FDA in 1999, orlistat was marketed under the brand name Xenical. Unlike stimulant-based weight loss drugs, Xenical works in the digestive system to prevent about one third of the fat consumed in a meal from being absorbed. This unabsorbed fat is then excreted in the stool.

Orlistat's mechanism of action made it unique among weight loss drugs, sidestepping the systemic side effects associated with stimulant-based drugs. It was touted as a breakthrough in the treatment of obesity, allowing people to lose weight without experiencing the stimulant side effects common to other diet pills.

Alli: Over-the-Counter Weight Loss

In 2007, GlaxoSmithKline (GSK) introduced Alli, a lower-dose, over-the-counter version of orlistat. Alli was met with much fanfare as the first FDA-approved over-the-counter weight loss drug. Its lower dosage (60 mg vs. Xenical's 120 mg) aimed to reduce side effects while still providing weight loss benefits.

While Xenical and Alli have been shown to be effective in promoting weight loss, their use is not without concerns. The primary side effects are gastrointestinal in nature, including oily stools and flatulence, which can be severe enough to cause discomfort and embarrassment. These side effects can be minimized by adhering to a low-fat diet.

The Role of Xenical and Alli Today

Today, Xenical and Alli remain popular options for individuals seeking to lose weight, offering a non-stimulant approach that differs from the majority of prescription weight loss drugs. They are especially suited to individuals who are prepared to make dietary changes, as the effectiveness and tolerability of these drugs are significantly enhanced with a low-fat diet.

In conclusion, the story of Xenical and Alli underscores the diversity of approaches to weight loss, highlighting the importance of tailoring weight management strategies to individual needs and circumstances. As part of the broader landscape of weight loss treatments, they represent a valuable option for those seeking a non-stimulant approach to weight management.

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