Last Updated January 22, 2024

 January 22, 2024

Curious how long does Melanotan 2 take to work?

Then stick around, as among the numerous research peptides that are currently under review for their possible benefits, melanotan 2 (MT-II) is one of the most promising.

In clinical trials, the a-MSH analog has been linked with numerous desirable effects and relatively few adverse reactions. This article will detail current findings on the potential therapeutic benefits of MT-II, including its documented latency periods, possible side effects, and best practices for researchers.

Plus, we will provide researchers with the best online source for purchasing top-grade melanotan 2. Read on to become an expert in this leading-edge peptide, from its physiological function to the proper methods of implementation in research.

Buy Melanotan 2 from our top-rated vendor...

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What is Melanotan 2?

Melanotan 2 (MT-II) has been evidenced in numerous studies to exhibit a range of therapeutic applications, including sunless tanning, neuroprotective effects, and improved sexual health [1, 2, 3].

MT-II is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH), an endogenous neuropeptide and melanocortin agonist that affects many important biological processes. The melanocortin system is comprised of five distinct receptors that regulate functions such as melanogenesis, sexual arousal, and inflammatory response [4, 5].

Structurally, MT-II is classed as a cyclic heptapeptide, displaying a lactic ring and truncated form. MT-II primarily affects melanocortin receptor 1 (MC1R) and melanocortin receptor 4 (MC4R), which respectively modulate melanogenesis and sexual behavior. It additionally interacts with the MC3R receptor to influence energy expenditure and metabolic processes [4, 5, 6].

Melanotan 2 behaves similarly to its parent hormone, yet to a greater degree as it is 1000% more potent. Originally developed as a synthetic tanning agent, it has since undergone clinical analysis in a wider range of potential therapeutic contexts [5, 6].

Related Peptides

Related derivatives of α-MSH are also under clinical evaluation, such as fellow melanocortin agonist melanotan 1 (MT-I). A precursor to MT-II, MT-I is a linear tridecapeptide that acts primarily on MC1R to elicit tanning effects, among other distinct functions.

A more modified derivative of α-MSH called PT-141 is also the subject of ongoing research and has been approved to treat low sex drive among premenopausal women [7, 8].

Emerging studies indicate multiple useful contexts for the administration of melanotan 2. Continue reading as we uncover these additional benefits, as well as possible side effects, optimal dosages, and the best source for researchers to purchase quality melanotan 2.

melanotan 2 take to work

Melanotan 2 Benefits | The A-Z Guide

Clinical research has indicated several key benefits of melanotan 2, namely:

Increased Melanin Production for a Tanning Effect

MT-II upregulates melanogenesis through its action at the MC1R receptor, increasing melanin production to darken the skin. The melanotropic agent also has photoprotective effects, shown to counteract photodamage and acute dermatoses from UV exposure in vulnerable subjects [1, 7].

Sexual Function

Its activation of the third and fourth melanocortin receptors lends MT-II the potential to enhance sexual response in both male and female subjects, with particularly notable effectiveness in treating symptoms of male erectile dysfunction [3, 9, 10].

Cognitive and Behavioral Health

In its capacity as an MC4R agonist, MT-II has been linked in animal studies with reductions in autistic and addictive behavioral patterns. Researchers posit that this is due in part to the receptor’s upregulation of oxytocin, known to modulate antisocial behaviors such as social attunement and communication difficulties, as well as impulsivity [2, 11].

Reduced Appetite

Several animal studies have revealed further effects of MT-II’s activity on melanocortin receptor 4, including diminished appetite as well as modified macronutrient preferences. The latter entails a reduction in fat and sugar consumption. This indicates the potential use of MT-II to treat obesity [12].


MT-II’s activity on melanocortin receptors 3 and 4 is evidenced to regulate blood glucose levels, suggesting its potential to counteract the effects of various metabolic diseases [13].

Body Composition

The role of the melanocortin system in fat storage and energetic expenditure suggests MT-II’s further effectiveness as a treatment for obesity. Clinical research involving animal subjects has linked MT-II with reduced adiposity [14].

Promising research into further potential therapeutic applications of MT-II is ongoing.

Melanotan 2 Side Effects

Melanotan 2 has been shown to elicit some side effects in clinical trials. Most side effects are minor, and there is a current lack of data on long-term side effects due to the peptide’s relatively novel status.

In one two-week trial involving three male subjects who received daily MT-II injections of 0.01 mg/kg, these side effects were reported [1] :

  • Fatigue and drowsiness
  • Spontaneous erections
  • Stretching and yawning repeatedly
  • Nausea ranging from moderate to severe

Further studies link MT-II with the development of moles as well as the increased pigmentation of pre-existing ones. Additional secondary effects include [7]:

  • Patchy skin pigmentation
  • Streaks of pigmentation in the nails
  • Flushing of the face
  • Changes in taste
  • Headache

Severe side effects are uncommon and have included [7]:

  • Abdominal pain
  • Hyperventilation
  • Hematoma
  • Heart palpitations
  • Acute priapism necessitating medical intervention
  • Melanoma
  • Dizziness
  • Seizures

Specialists discourage MT-II administration in subjects with symptoms of body dysmorphia, especially regarding skin tone. Most of the noted side effects are transient and cease with the termination of MT-II injections. They are also linked with factors such as comorbidities, drug interactions, and the use of artificial tanning beds.

Adverse effects are also significantly linked to improper dosage and contaminated peptides, typically sourced from disreputable vendors. Low-quality melanotan 2 products can include hazardous contaminants that lead to acute systemic toxicity. Thus, experts strongly advise that researchers acquire MT-II from strictly trusted sources and firmly abide by standard dosing guidelines [7].

While the information on long-term melanotan 2 use is pending, it is regarded by clinical specialists to have a favorable safety profile under proper conditions and handling.

How Long Does Melanotan 2 Take to Work?

The rates of effectiveness in melanotan 2 vary depending on the desired therapeutic outcomes. Further, some potential benefits are evidenced only in clinical trials involving animal subjects, revealing latency periods that may change in human subjects.

With such factors in mind, here are the current findings on the primary evidenced benefits of melanotan 2:

Tanning [1, 7, 15]

In many clinical trials on human subjects, melanotan 2 has been proven as an effective synthetic tanning agent, rendering optimal results in concert with scheduled windows of UV exposure. While trial lengths vary, most have yielded visible tanning results within one to two weeks of daily injections. These findings are dose-dependent.

Although visible tanning effects show some latency, research has shown the photoprotective benefits of MC1R stimulation to be immediate.

Sexual Health [4, 16, 17]

The pro-erectile effects of MT-II in both animal and human studies are well-documented, owing to its affinity for melanocortin receptors 1, 3, and 4. In one important study, ten men with psychogenic ED were given MT-II injections of 0.025 to 0.157 mg/kg. Eighty percent of the subjects developed erections of notable duration and rigidity with latency periods ranging from 15 to 270 minutes. Another study on men with organic ED yielded similar results. Increased sensations of sexual desire were also reported.

The role of melanocortin receptors 3 and 4 in boosting sexual arousal in females has also been noted. A synthetic peptide and MT-II derivative called PT-141 has been proven to increase sexual response in premenopausal women within 24 hours of administration.

Behavioral and Cognitive Effects [2, 18, 19]

In a study on male mice exhibiting autism features per the MIA model, a complete reversal of autistic behavioral features was observed within seven days of daily MT-II administration. This suggests the potential of MT-II as a rapidly effective autism treatment.

Regarding addictive behavior and effects, MT-II has been shown to diminish alcohol consumption while reducing its neurotoxic effects in animal studies. In one of these, alcohol-seeking behavior was immediately reduced and curtailed for up to 24 hours after MT-II injection. This is theorized to be affected through MC3R and MC4R stimulus and is thought to pertain to additional addictive substances, pending further research.

Appetite Reduction [20, 21]

Several studies involving animals have shown that MT-II injections can significantly decrease appetite and modify macronutrient preferences within 24 hours of administration.

Metabolic Health [13, 22]

While one animal study showed MT-II to modulate insulin sensitivity within 24 hours of injection, another showed significant improvements in insulin sensitivity after 10 days of continuous administration in obese rats.

Body Composition [14, 22, 23]

Additional studies in rodents indicate the effectiveness of MT-II in weight loss and reducing body fat. In one study, a 40-day trial of daily MT-II administration in rats yielded significant decreases in body fat and adiposity in all subjects. This included increased thermogenesis.

Melanotan 2 Dosage Guide

These are the dosage and injection guidelines that experts agree upon when administering melanotan 2 [1, 7]:

  • The base therapeutic dose for the subcutaneous injection of MT-II is 500 mcg per day.
  • It is recommended to start with a low dose and gradually increase it to minimize side effects.
  • The maximum dose seen in clinical trials is 1mg/kg daily.
  • Trials range from one to more weeks. The indefinite use of MT-II is not recommended. Administration schedules vary from one to several weeks.
  • To maximize tanning benefits, it is recommended to inject MT-II before regular UV exposure sessions of 60 minutes or less.
  • Tiered dosing frequency is recommended, starting with a loading phase and then proceeding to a maintenance phase.


To correctly reconstitute melanotan 2 for injection, the following items are required:

    • Vial of bacteriostatic water
    • Vial of lyophilized MT-II
    • Alcohol wipes
    • Sterile syringe


The process of MT-II reconstitution before an injection is as follows:

Step 1. Wipe all items down with alcohol to reduce the risk of contamination. This includes the uncapped vials.

Step 2. Using the syringe, withdraw a small amount of bacteriostatic water, usually 1-2 mL. The exact amount depends on the dose.

Step 3. Gradually inject the bacteriostatic water into the vial of MT-II, allowing it to slowly drip down the side and evenly dissolve the powder.

Step 4. Avoid stirring or shaking the vial, as doing so may damage the peptides. When it is fully mixed, the solution will be transparent.

Properly store and refrigerate excess solution for subsequent injections.

Click here to learn more about Melanotan 2 dosages!

Melanotan 2 Cycle | A-Z

Melanotan 2 is not indicated for indefinite use and should be administered in cycles of varying lengths and quantities, depending on desired therapeutic outcomes. In clinical trials, duration and dosage specifics vary widely, so researchers are advised to familiarize themselves with the latest studies and best practice guidelines.

When it comes to injecting MT-II for sunless tanning, specialists agree that it is best to start at a low dose and gradually increase, moving between loading doses and maintenance doses. Let’s explore these phases [7, 24]:

Starting Dose

The starting dose can be as small as 250mcg and is intended to allow the assessment of the subject’s reaction. Ideally, it would elicit no noticeable effects.

Loading Dose

If no acute adverse reactions are noted, the dosage can be increased gradually to 500mcg-1mg daily. During this phase, regular UV exposure will result in visible tanning.

Maintenance Dose

This phase begins when the subject has obtained the desired level of tanning. The frequency of administration can be cut down to as little as once a week, and the dosage may be modified.

Depending on the skin type of the subject, visible tanning effects should last for up to several months after cessation of the therapy. While there is no standard indication for the duration of use, most clinical trials last from one to several weeks.

melanotan 2 take to work

Where to Buy Melanotan 2 Online? | 2024 Edition

When it comes to incorporating melanotan 2 into a research study, it is crucial to source materials strictly from a quality vendor. Those unsure of where to start need to worry!

The team of passionate experts here at is happy to name our number-one choice for purchasing superior melanotan 2 online.

Our vast market research has revealed this vendor as the leading provider of melanotan 2 and other premium research peptides:


Here are the reasons why PureRawz rises above alternative retailers:

  • Quality Assurance: The quality of all compounds is guaranteed and verified via third-party lab reports that establish minimum 99% purity levels for products included in the vendor’s catalog.
  • Excellent Prices: Premium peptides are sold at great prices. A single 10mg vial of MT-2 is only $57, and the site offers price reductions based on payment methods and other factors.
  • Quick Shipping: Shipping is quick and affordable, offered to many locations worldwide. Orders that exceed $100 are shipped free of charge for 3-day delivery within the United States. International shipments arrive in 7-21 days and fees vary depending on the destination.
  • Fast Checkout: The SSL-secured website enables smooth and safe checkout, accepting most forms of payment for the client’s convenience.
  • Customer Support: Clients enjoy first-rate customer service from qualified agents that quickly respond to all customer requests within just 24 hours.

Enjoy the many benefits of purchasing prime melanotan 2 from PureRawz, the uncontested source of superior research materials for leading scientists across the world.

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Does Melanotan 2 Work? | Verdict

This concludes our comprehensive exploration of melanotan 2, one of the most exciting research peptides on the market today. Its numerous therapeutic potentials have been clearly evidenced in both animal and human trials.

Effects such as enhanced tanning, sexual health improvements, and weight loss are observed with small latency windows, indicating both the speed and potency of melanotan 2 when properly handled.

Emerging research is constantly uncovering even greater benefits and wider applications for this innovative peptide. Whether the research is intended to focus on just one benefit or many, the rapid effects of melanotan 2 may be noted, especially when sourced from a trusted vendor with quality guaranteed.

Buy Melanotan 2 from our top-rated vendor...


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  11. Lerma-Cabrera JM, Carvajal F, Garbutt JC, Navarro M, Thiele TE. The melanocortin system as a potential target for treating alcohol use disorders: A review of pre-clinical data. Brain Res. 2020 Mar 1;1730:146628. doi: 10.1016/j.brainres.2019.146628. Epub 2019 Dec 28. PMID: 31891691; PMCID: PMC7023989.
  12. van der Klaauw A, Keogh J, Henning E, Stephenson C, Trowse VM, Fletcher P, Farooqi S. Role of melanocortin signalling in the preference for dietary macronutrients in human beings. Lancet. 2015 Feb 26;385 Suppl 1(Suppl 1):S12. doi: 10.1016/S0140-6736(15)60327-0. PMID: 26312834; PMCID: PMC6548551.
  13. Heijboer AC, van den Hoek AM, Pijl H, Voshol PJ, Havekes LM, Romijn JA, Corssmit EP. Intracerebroventricular administration of melanotan II increases insulin sensitivity of glucose disposal in mice. Diabetologia. 2005 Aug;48(8):1621-6. doi: 10.1007/s00125-005-1838-8. Epub 2005 Jun 22. PMID: 15971058.
  14. Strader AD, Shi H, Ogawa R, Seeley RJ, Reizes O. The effects of the melanocortin agonist (MT-II) on subcutaneous and visceral adipose tissue in rodents. J Pharmacol Exp Ther. 2007 Sep;322(3):1153-61. doi: 10.1124/jpet.107.123091. Epub 2007 Jun 13. PMID: 17567964.
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  21. Glavas M, Joachim S, Draper S, Smith S, Grove KL. Melanocortinergic Activation by Melanotan II Inhibits Feeding and Increases Uncoupling Protein 1 Messenger Ribonucleic Acid in the Developing Rat [Internet]. Endocrinology. Oxford University Press; 2007 [cited 2022Nov10]. Available from:
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  24. Complete MT 2 info / melanotan 2 tanning injections [Internet]. Lovemelanotans. [cited 2022Nov10]. Available from:

Scientifically Fact Checked by:

David Warmflash, M.D.

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