Retatrutide Dosage Guide For Weight Loss: What We Know So Far

Retatrutide is one of the most anticipated new medications in the world of weight management. As research continues, many people are keen to understand how it works, the correct dosage and what results it might bring. The insights in this article are provided by Vivere's Head of Nutrition, Yusra Serdaroglu Aydin, a registered dietitian with a background in nutrition, food engineering and culinary arts. Her approach is grounded in science and shaped by a strong understanding of personalised nutrition and the human microbiome.

This guide explains what retatrutide is, how it is used and what to expect in terms of dosage, benefits and side effects, based on the latest scientific evidence available.

“Retatrutide, also known as Triple G, is a once-weekly injectable medication currently being researched for weight loss and Type 2 diabetes, showing promising results in early studies by targeting multiple metabolic pathways involved in appetite control and fat metabolism”.

Here are the five biggest takeaways from this article about retatrutide dosage:

• Retatrutide is an investigational weekly injection designed to aid weight loss and improve metabolic health.

• It acts on three key hormonal pathways to help reduce appetite and support fat burning.

• Clinical trials suggest significant weight reduction, though it is not yet approved for use.

• The dosing schedule is gradual to minimise side effects, similar to other GLP-1 medications.

• A balanced diet, regular exercise and healthy lifestyle habits remain essential for sustainable results.

Retatrutide is a once-weekly injectable medication currently in development for weight management and metabolic disorders. It works by activating three different receptors in the body (GLP-1, GIP, and glucagon receptors). This triple-action approach helps to control appetite, regulate blood sugar levels and support fat metabolism.

Unlike earlier medications such as semaglutide or tirzepatide, which act on one or two receptors, retatrutide’s triple mechanism may make it more effective for people struggling with obesity or insulin resistance.

In clinical studies, retatrutide has demonstrated significant potential. According to research, participants experienced substantial weight reductions, with some losing over 20% of their body weight over 48 weeks [1] [2].

Early research suggests that retatrutide may offer multiple benefits beyond weight loss. Because of its triple-action mechanism, it appears to have a broader metabolic impact compared with traditional GLP-1 agonists like Wegovy and Mounjaro.

The potential benefits may include [1]:

• Significant weight loss through reduced appetite and improved fat metabolism.

• Better blood sugar control, which may support individuals with prediabetes or type 2 diabetes.

• Improved cardiovascular health, as losing excess body fat can reduce strain on the heart and lower cholesterol levels.

• Enhanced metabolic efficiency, helping the body to use stored fat for energy rather than relying solely on glucose.

Like other injectable medications in its class, retatrutide is administered just under the skin (subcutaneously) once a week. The injection is expected to be delivered via a pre-filled pen, similar to other GLP-1-based treatments such as Wegovy and Mounjaro.

Once available, users will likely attach a small disposable needle to the pen before injection. The medication is injected into areas with a layer of subcutaneous fat, such as the abdomen, thigh, or upper arm.

The dosing schedule for retatrutide is designed to start gradually, allowing the body to adapt to the medication and minimise side effects such as nausea.

Clinical trials have generally begun with a low starting dose, which is increased every few weeks until the target dose is reached. This approach helps improve tolerability while still achieving effective results over time.

Although exact dosing schedules may vary depending on the final approved formulation, it is likely that retatrutide will follow a similar model to other GLP-1 and dual-agonist drugs, increasing in small amounts during the first few months of treatment.

Once the target dose is reached, patients will likely move to a maintenance dose, which is then continued weekly to maintain weight loss and metabolic benefits.

Like all medications that affect the digestive and metabolic systems, retatrutide may cause side effects, particularly when treatment begins.

The most commonly reported effects are mild to moderate digestive symptoms, which tend to improve as the body adjusts. These may include:

• Nausea

• Vomiting

• Diarrhoea

• Constipation

• Reduced appetite

These reactions are similar to those seen with other GLP-1 receptor agonists and often lessen over time.

More serious side effects appear to be rare but could include pancreatitis or gallbladder issues, as seen in similar medications. Because research is ongoing, it is essential to follow medical advice and report any unusual symptoms promptly.

While retatrutide shows promise, lasting weight management depends on more than medication alone. Sustainable results come from a balanced approach that includes nutrition, movement and lifestyle habits.

At Vivere, we recognise that every person’s body is different. Understanding your gut microbiome, nutrient needs and metabolic responses can help you make informed choices that support long-term health. This can be achieved using a Vivere gut microbiome test and personalised nutrition plan.

Evidence shows that focusing on nutrient-dense whole foods, understanding your relationship with food, and supporting your metabolism through science-backed supplements can enhance results [3] [4] [5].

“Retatrutide is an exciting development in medical weight management, with research showing that it could help people achieve meaningful weight loss. By acting on multiple metabolic pathways, it may offer advantages over existing medications. However, it is still under study and should not be seen as a substitute for a balanced diet or a healthy lifestyle.

Combining evidence-based medical treatments with personalised nutrition and microbiome support remains the most effective way to achieve lasting results”.

Vivere helps you take control of your health with personalised insights from state-of-the-art gut microbiome testing, nutritional guidance, science-backed supplements, NAD+ injections and expert support. Sign up today and start living better, for longer.

[1] The power of three: Retatrutide's role in modern obesity and diabetes therapy - ScienceDirect

[2] Triple–Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial | New England Journal of Medicine

[3] Biohacking: The 7 Best Foods For Weight Loss - Vivere

[4] Orthorexia: When Healthy Eating Becomes Harmful - Vivere

[5] Top Emerging Supplements to Watch in 2025 - Vivere