Melanotan II vs PT-141: the best peptide for erectile dysfunction

Melanotan II vs PT-141, which peptide is superior for erectile function?

Are you struggling with erectile dysfunction and searching for the best peptides to address this issue? Look no further! In this article, we will explore the effectiveness of Melanotan II and PT-141 in treating erectile dysfunction. Both of these peptides have gained popularity among men seeking enhanced sexual performance.

But which peptide is the best for addressing erectile dysfunction? In this comprehensive comparison, we will delve into the mechanism of action, effectiveness, possible side effects, and overall user experiences of Melanotan II and PT-141. By the end of this article, you’ll have a clear understanding of which peptide may be the ideal solution for your specific needs.

Whether you’re considering Melanotan II or PT-141, this article will provide you with valuable insights to help you make an informed decision when it comes to treating erectile dysfunction with peptides. So, let’s dive in and discover the best peptide for you!

Understanding erectile dysfunction (ED)

Erectile dysfunction, commonly referred to as ED, is a condition that affects millions of men worldwide. It is characterized by the inability to achieve or maintain an erection sufficient for sexual intercourse. ED can have a significant impact on a man’s self-esteem and overall quality of life.

Various factors can contribute to the development of erectile dysfunction, including age, underlying medical conditions, lifestyle choices, and psychological factors. While there are several treatment options available, peptides like Melanotan II and PT-141 have shown promising results in addressing this issue.

What are peptides?

Before we delve into the effectiveness of Melanotan II and PT-141, let’s first understand what peptides are. Peptides are short chains of amino acids that play a crucial role in various physiological processes in the body. They act as signaling molecules, regulating the activity of cells and tissues.

Insulin is a peptide released by the beta-cells of the pancreas to help with glucose handling.

BPC-157 is another popular peptide used by athletes to speed up the recovery of an injury.

In recent years, peptides have gained popularity in the field of medicine and performance enhancement due to their ability to target specific receptors and produce desired effects. Peptides have been extensively studied for their potential in treating various conditions, including erectile dysfunction.

How do Melanotan II and PT-141 work for erectile dysfunction?

Now that we have a basic understanding of peptides, let’s explore how Melanotan II and PT-141 work to address erectile dysfunction.

Quick overview of the melanocortin system

Both Melanotan 2 and PT-141 work through the melanocortin system of the body. The natural agonist of the melanocortin receptors is alpha-melanocyte stimulating hormone (α-MSH).

It all starts with POMC (pro-opiomelanocortin), which is mostly synthesized in the anterior pituitary gland. It’s also created in the hypothalamus, brain stem and skin (you’ll see why this is important later on).

POMC is a polyhormone (a long chain of amino acids) that is cut (cleaved) to give rise to at least 8 distinct peptides. 3 important ones include:

  • α-MSH, which is produced by neurons in the ventromedial nucleus. It plays am important role in satiety, sexual arousal (and promotes sexual activity) and melanin produced from melanocytes in the skin.
  • ACTH, which stimulates the adrenal glands to release cortisol, DHEA and aldosterone.
  • β-Endorphin and enkephalin, which are opioid peptides involved in pleasure and euphoria.

α-MSH then binds to melanocortin receptors of which there are 5. These receptors regulate many important physiological functions including food intake, energy homeostasis, and immune function. Melanocortin receptors 3 and 4 are the ones mainly involved in libido and erections.

Both α-MSH and ACTH, known as the melanocortins, play a role in penile erection and sex behavior in animals and humans (R).

α-MSH and ACTH are believed to act downstream from dopamine and oxytocin (R). Meaning, dopamine and oxytocin promote the release of POMC and the creation of α-MSH and ACTH.

Back to melanotan 2 and PT-141 mechanism of action

Melanotan II functions by stimulating melanocortin receptors in the body, specifically the MC1R and MC4R receptors. Activation of these receptors leads to increased production of melanin, the pigment responsible for skin color. However, Melanotan II’s effects on sexual function are not solely related to pigmentation.

Melanocortin receptors are also present in the brain, where they regulate sexual arousal and desire. By activating these receptors, Melanotan II enhances sexual desire and improves erectile function. It is important to note that Melanotan II should not be confused with the original Melanotan, which was developed solely for tanning purposes.

On the other hand, PT-141 works by activating melanocortin receptors in the brain. Unlike Melanotan II, PT-141 does not have a direct effect on skin pigmentation. Instead, it specifically targets the MC4R receptor in the brain, which plays a crucial role in sexual arousal and response.

By stimulating the MC4R receptor, PT-141 enhances sexual desire and improves erectile function. It is worth mentioning that PT-141 is currently undergoing clinical trials for the treatment of female sexual dysfunction as well.

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Melanotan II effectiveness for erectile dysfunction and low libido

Melanotan II injections are very effective at promoting erections. Based on 2 clinical trials in men with psychogenic and organic ED injected with Melanotan II at 0.025mg/kg (R):

  • Between 63 and 85% of the men got proper erections.
  • 63% of the men experienced a significant increase in sexual desire and sex drive.
  • Most men were able to hold an 80% erection for 41-45.3 min (R, R). 41 to 45.3 min is a long duration. That’s pretty good!

Melanotan dose and timing for erections

Melanotan 2 has a half-life of ~33 hours, this allows you to be very flexible with dosing. So you can take it in the morning or in the evening, it really doesn’t matter.

According to ChemicalBook, the recommended starting dose is 250mcg every day to help your body acclimatize to the peptide and minimize the side effects. You can continue with this dose indefinitely if you intend to do a low-dosage regimen (R).

If you want to use a higher dose, whenever you feel comfortable (minimal side effects), up the dose to 500mcg. 500mcg is the most common dosage amount administered by users (R). 

In the 2 studies above, they use 0.025mg/kg (e.g. 2.5mg for 100kg guy) subcutaneous injection every 48 hours. The effects might be cumulative, meaning, the 6th dose will usually be better than the 1st (R). This dose is much higher than what is generally recommended (250mcg).

If 250 to 500mcg (0.25-0.5 mg dose) doesn’t do the trick for you, then increase the dose slowly by 250mcg. Don’t take large doses every day, but rather once or twice a week due to the long half-life.

The recommended dose for skin tanning is 0.1mg/kg (R).

Will Melanotan II work even if I have normal testosterone?

The effects of melanotan 2 will likely be less effective if your testosterone is low (<300ng/dl) (R).

In this study, they gave 20 men with psychogenic (450ng/dl average testosterone) and organic (362ng/dl average testosterone) ED Melanotan II, and it was equally effective in both groups (R).

Positives that you can expect from Melanotan II

  • Spontaneous erections
  • Stronger erections (leading to better sexual performance and sexual satisfaction)
  • Erections that last longer
  • Enhanced orgasm pleasure
  • Enhanced libido / sexual motivation

Side effects that you can expect from Melanotan II

  • Facial flushing
  • Reduced appetite (this can be a benefit for weight loss)
  • Yawning (R).
  • Stretching (R).
  • Nausea: the occurrence of this is low (12.9%) at the recommended dose of 0.025mg/kg. In rare cases, vomiting (R).
  • Priapism: painful erections for longer than 4 hours without sexual stimulation (R).
PT-141 ED

PT-141 (AKA Bremelanotide) for erectile dysfunction and low libido

PT-141 is a metabolite of Melanotan II and doesn’t have to be injected. It was originally designed in the United States and approved by the United States Food and Drug Administration for women with hypoactive sexual desire disorder. Later on, it was also marketed to men as an effective tool for ED treatments.

It’s mainly taken intranasally (via nasal spray) since oral absorption is very poor at around 14% (R). Also, the faster it can cross the blood-brain barrier, the faster it can give you results. Taking it intranasally is a good way to shorten the onset time.

Where Melanotan II is a non-selective melanocortin receptor agonist, PT-141 is an agonist at melanocortin receptors MC3-R and MC4-R, which are primarily expressed in the central nervous system (R).

When and how often to take PT-141

The half-life of PT-141 is only around 2 hours so it can be taken more frequently (R). For the best results, take it 30-60min before sex.

PT-141 half life

The effectiveness (and side effects) of PT-141 is very similar to Melanotan II.

PT-141 dosing for erectile dysfunction

A good starting dose is 7mg and then you can work up from there. This study found that 4mg was ineffective, whereas the effective dose started at 7mg. The highest dose tested was 20mg.

The higher dose you use, the faster the onset and the stronger the effects will be. This counts for both the benefits (erection and desire) and side effects (flushing and nausea).

E.g. when they increased the dose from 7 to 20mg, the average erection increased from 49.4 to 137.7 min (R).

In short, PT-141 works!

PT-141 dose on erectile duration

Benefits of PT-141

  • Faster onset: the onset of the first erection occurs in approximately 30 min (as opposed to 2 hours for Melanotan 2).
  • Doesn’t have to be injected (it’s taken intranasally)
  • The half-life is shorter. If you do get any side effects, they don’t last as long. For most people, it lasts 2-6 hours.
  • It doesn’t affect nitric oxide or work via the vascular system or affect blood flow, thus it doesn’t affect blood pressure.

Can I take PT-141 with Viagra or Cialis?

Yes, they work synergistically together, and then you can take smaller doses of each.

This study found that men got significantly better erections when they used PT-141 and sildenafil (25 mg sildenafil and 7.5 mg intranasal PT-141) together compared to sildenafil alone (R).

The benefit of combination therapy is that you can use smaller doses of each which limit the side effects. “Co-administration of PT-141 and sildenafil was safe and well-tolerated and did not result in new adverse events or adverse events that were increased in frequency or severity compared with monotherapy.” (R).

Alternative to Melanotan II or PT-141

The dopamine and norepinephrine reuptake inhibitor anti-depressant Bupropion (Wellbutrin) + opioid antagonist naltrexone work via the POMC pathway to reduce appetite, increase energy expenditure and potentially promote sexual function (R).

Boosting POMC (and α-MSH) naturally

Sunlight and sunlight. Bright light acts on the skin and through the eyes into the hypothalamus to produce POMC.

Plus, in the summer, there is more sunlight and the days are longer. This enhances the conversion of thyroid pro-hormone T4 into the active hormone T3. T3 also enhances POMC production.

Related article:

Where to buy Melanotan II and PT-141 peptides

PT-141 sources

Melanotan 2 sources


What works fast for erectile dysfunction?

PT-141, which, when taken intranasally, will start working within 20-30 minutes. You can combine that with low-dose Cialis for even stronger erections.

Will peptides make you bigger?

If someone is unable to get a full erection they will look smaller than their true potential. If they are able to get a full erection with melanotan 2 or PT-141, it will make them bigger.

How long should you be on peptides?

As long as you get the benefits. If you feel like the benefits are waning, then it’s good to take 2-3 weeks off, then try them again.

How long does it take for PT-141 to kick in?

PT-141 starts to work within 20-30 minutes.

How often can I use PT-141?

PT-141 has a half life of about 2 hours, so it can be taken every 3-4 hours to maintain steady levels, but that might lead to more side effects. Since PT-141 has such as short half life, you could take it daily or morning and evening, depending on how much sex you’re going to have.

Summary – the best peptides for erectile dysfunction

There are many ED medications and peptide treatments are one of them. Combining low-dose Cialis (5mg) with low-dose PT-141 peptide therapy (7-10mg) is likely best to eliminate most of the side effects.

Additionally, I’d focus on getting lots of sunlight and perhaps add a strong natural anti-oxidation that can also help with erections, namely pycnogenol. Pycnogenol with arginine has been shown to resolve 95% of ED cases in just 3 months. I prefer to use citrulline instead of pycnogenol, but you can use pycnogenol by itself as well.


Check out my ED article series: Erectile dysfunction part 1

>1000ng/dl Testosterone: My Step-by-Step Guide on How I Do It Naturally!

3 thoughts on “Melanotan II vs PT-141: the best peptide for erectile dysfunction”

  1. Hi Hans, thank you very another great article.
    I’ve tried many different brands of pycnogenol, but it doesn’t seem to help. It seems to have an estrogenic type response with me.
    Can the active ingredients in pycnogenol increase estrogen?

    • Thanks man! What dose did you use? Pyconogenol is the active ingredient of maritime pine bark. Too large doses of a lot of plant compounds can be estrogenic. Low doses are usually anti-estrogenic, whereas high doses might be estrogenic.


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