PT-141 Pen
A cyclic seven amino acid melanocortin receptor agonist, derived from work on melanotan II. Approved in the United States as Vyleesi. This pen holds 10mg, already in solution.
Why it is being studiedMelanocortin receptors. Acts at the melanocortin receptor family, principally MC4R.
Approved indication. Licensed in the United States for hypoactive sexual desire disorder in premenopausal women.
Central, not vascular. Acts in the nervous system rather than on blood vessels.
Mostly preclinical research. Human data is limited, and nothing here establishes an effect in people.
£380.00 Original price was: £380.00.£342.00Current price is: £342.00.
Before you start
Check the batch number on the pen against the certificate of analysis on this page. If they don't match, don't use the pen. Contact us and we'll replace it.
Inspect the solution through the window. It should be clear and free of particles. Copper peptide solutions are blue, and that colour is expected. Cloudiness, discolouration or visible matter means the pen should not be used.
The pen
Each pen arrives pre-filled, in solution, at the concentration on the label. There is nothing to reconstitute, no bacteriostatic water to add and no concentration to calculate.
The dose counter is mechanical. Turning the dial advances it one increment at a time, with an audible click per increment, and the number in the window is the amount set. The counter cannot be turned past the volume remaining.
Pens take standard pen needles, supplied with your order. Fit a fresh one each time and remove it afterwards. Leaving a needle attached lets air into the cartridge and can affect what the counter reads next.
Storage
Refrigerate at 2–8°C on arrival and keep the pen in its carton. Peptides in solution degrade faster in light, and copper peptides faster still.
Do not freeze. Freezing damages peptides in solution and the pen cannot be relied on afterwards, whatever it looks like.
Return the pen to refrigeration between uses once the seal is broken. A cold pen is stiffer to dial, so leaving it out for a few minutes beforehand makes the counter turn more smoothly.
Disposal
Used needles go into a sharps container, not household waste. UK pharmacies and local councils both supply them, and most councils collect full ones on request.
Supplied for laboratory research use only. Not for human or veterinary use, and not a medicine. Nothing on this page describes a protocol, a schedule or an application, and none should be inferred.
Every batch is tested before release
No batch reaches our shelves without a report from an independent laboratory. Testing is done by a third party with no commercial interest in the result, not by us and not by the manufacturer.
What the certificate shows
Identity, confirming the compound is what the label says it is. Purity, measured by high-performance liquid chromatography and reported as a percentage. The date of testing and the batch number the result applies to.
How to check it yourself
Every pen carries a batch number, and the certificate on this page carries the same number. If the two don't match, something has gone wrong in our dispatch and we want to hear about it. We'll replace the pen.
Certificates are published as the laboratory issued them. We don't retype results, summarise them or crop the report.
Cold chain
Stock is held refrigerated and ships in insulated packaging with a cold pack. Orders are dispatched so they travel over the shortest practical window rather than sitting in a depot over a weekend.
If a pen arrives damaged, warm, or not matching its certificate, contact us within 48 hours of delivery and we'll replace it.
How is it related to melanotan II?
It came out of the same research. Melanotan II acts strongly at MC1R, the pigmentation receptor. PT-141 is a related compound that acts principally at MC4R in the brain.
Is it the same as the prescription product Vyleesi?
Vyleesi is the approved formulation of bremelanotide, supplied as a prescription medicine with its own labelling and prescribing information. This is the compound supplied for research use and is not that product.
Is it related to KPV, also in your range?
Distantly. Both trace back to melanocortin biology, but KPV is the tail fragment of alpha MSH and does not act at these receptors.
Is this prohibited in sport?
It is not named on the World Anti-Doping Agency prohibited list, but WADA also bans substances with no current approval for human therapeutic use under S0. Check the current list yourself if you are tested.
Why is the solution clear rather than blue?
Blue solutions in our range are the copper complexes, GHK-Cu and AHK-Cu. This one in solution is clear. Cloudiness or visible particles mean the pen should not be used.
How many doses are in a 10mg pen?
That depends entirely on the increment you dial, so there is no single answer. The counter shows what is set and the pen cannot be turned past the volume remaining.
Store at 2–8°C
Refrigerate on arrival and keep the pen in its carton, away from light.
Cold-chain shipped
Insulated packaging with a cold pack, in a plain outer box with no reference to the contents.
Never freeze
Freezing damages peptides held in solution. A frozen pen cannot be relied on afterwards.
Third-party tested
Every batch tested by an independent laboratory for identity and purity by HPLC.
Batch traceable
The batch number printed on the pen matches the number on its certificate.
Certificate on the page
Published exactly as the laboratory issued it. Not summarised, not on request.
Product Description
PT-141, also catalogued as bremelanotide, is a synthetic heptapeptide derived from the alpha-MSH sequence.
There is nothing to reconstitute. The compound arrives already dissolved at a known concentration, so there is no bacteriostatic water to add, no vial to swirl and no concentration to calculate. The dose is set on a mechanical counter that clicks as it turns, and the pen takes standard pen needles.
Every batch is tested by an independent laboratory before release. The certificate of analysis for this batch is published on this page and records identity, purity by HPLC and the date of testing. The batch number on the pen matches the batch number on the certificate.
Store refrigerated at 2–8°C and keep the pen in its carton, away from light. Do not freeze. Once the seal is broken, keep the pen refrigerated between uses and replace the cap after each use.
Ships in insulated packaging with a cold pack, in a plain outer box with no reference to the contents. Supplied for laboratory research use only. Not for human or veterinary use, and not a medicine.
How does it work
The melanocortin receptors are a family of five. MC1R governs pigmentation, which is what melanotan II was originally studied for. PT-141 came out of that work but acts principally at MC4R, which is expressed in the brain.
That distinction matters for how it is classified: it acts centrally, through the nervous system, rather than on blood vessels the way the PDE5 inhibitors do. Its approval in the United States covers one specific indication in one specific population.
Human trials exist for this compound but were run for a specific clinical question, not for general use. Nothing here is a recommendation and we make no claim of effect.
What’s included
- One pre-filled PT-141 pen, 10mg total content, supplied in solution
- Pen needles
- Storage and handling card
- Certificate of analysis, published on this page
- Insulated packaging with a cold pack
Specifications
- SKU
- NW-P-PT141-10
- Format
- Pre-filled pen, in solution
- Total content
- 10mg
- Compounds
- PT-141 (bremelanotide)
- Storage
- Refrigerate at 2–8°C
- Batch number
- NW-PT14-260925-A
