VLS Retatrutide Pen 20mg

📅 August 16, 2026 ⏱️ 3 min read ✍️ Team TPS

The VLS Retatrutide Pen is a pre-filled 20mg pen of the triple agonist, the newest and most aggressive of the GLP-1 generations.

What retatrutide is

Retatrutide agonises three receptors: GLP-1, GIP and glucagon. Semaglutide covers the first; tirzepatide covers the first two.

The glucagon addition is what separates it. Where GLP-1 and GIP act largely on appetite, insulin response and gastric emptying, glucagon receptor agonism brings energy expenditure in, the body spending more rather than only taking in less. See the three compared.

The pen format

The VLS Retatrutide Pen arrives pre-filled at 20mg. No reconstitution, no bacteriostatic water, no concentration decision, and the in-solution clock does not start until you fit a tip.

For a compound used in small amounts, removing the draw-by-eye step matters more than it sounds. Pen or vial covers the trade.

20mg is a total, not a dose

This is the thing to get right before touching the dial. The 20mg figure is what is dissolved in the cartridge. What one click delivers depends on that total, the cartridge volume, and how the dial divides it.

The same dial number on a 20mg pen and a 40mg pen delivers different amounts. Work the per-unit figure out once, how to read a peptide pen dial and how many doses are in a 10mg pen.

Expect the step-up

Retatrutide is not started at the amount you intend to end at. Tolerance to the gastrointestinal effects builds over time, and going too fast reliably produces a bad week and someone abandoning a compound that would have worked.

Nearly every side effect traces back to slowed gastric emptying. See GLP-1 side effects explained.

The honest trade

Retatrutide’s trial results have attracted attention for their magnitude. Tirzepatide’s evidence base is larger and older.

A more aggressive mechanism is more aggressive in both directions. See tirzepatide vs retatrutide for choosing between them, and GLP-1s and muscle retention for the thing that actually goes wrong on large effortless deficits.