Melanotan II Dosing: Protocol

Fase	Dosis	Frecuencia
Loading phase	200 mcg, up to 500 mcg	once a day Start at 200 mcg to gauge sensitivity before stepping up.
Maintenance	200 mcg	twice a week Once the research goal is reached.

Solely for handling in a research setting: the melanotan II protocol uses a loading phase of 200 mcg a day by the subcutaneous route, rising to 500 mcg a day, and then drops down to a maintenance of 200 mcg twice a week as soon as the intended pigmentation target has been reached. As of 2026, melanotan II is not authorised as a medicine, nor is it authorised for cosmetic use in humans [6][7].

Parameter	Value	Source
Loading dose	200 mcg a day, up to 500 mcg	Protocol
Maintenance dose	200 mcg twice a week	Protocol
Tmax after SC injection	~30 minutes	Not verified
Apparent terminal half-life	~1 hour	Not verified
Preferred administration window	In the evening (before sleep)	Methodology note
Regulatory status (2026)	Not authorised as a medicine	[6][7]

Melanotan II dosing: the essentials

The loading phase delivers 200 mcg a day, rising to 500 mcg a day; maintenance drops to 200 mcg twice a week
Subcutaneous injection between 22:00 and 23:00 reduces MC4R-mediated nausea by shifting the peak plasma concentration into the sleep period
Nausea, facial flushing and spontaneous erections are the dominant early reactions; a baseline dermatological record avoids any confusion with the darkening of pre-existing naevi
Melanotan II holds no marketing authorisation; all of the data set out below serve solely as an analytical reference for research
The dial on the 20 mg pen sets the dose directly in milligrams, with no need for prior calculations

What melanotan II is and how it works

Melanotan II is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone (α-MSH), with a molecular weight of 1,024.2 g/mol and CAS number 121062-08-6 (PubChem CID 92432). It is supplied solely as a reference compound for the purposes of research and analysis, and not as a medicine authorised for human use [6][7].

The peptide acts as a non-selective agonist of the melanocortin receptor family. Pigmentation and the off-target effects are driven principally by two of those receptors:

Receptor	Tissue / signal	Relevance to the protocol
MC1R	Melanocytes	Drives eumelanin synthesis; the pigmentation endpoint that researchers record [5]
MC4R	CNS (hypothalamus)	Appetite suppression, libido signalling, nausea; the adverse-effect window described further down [4][5]
MC3R / MC5R	Mixed peripheral	Minor contribution; not the target of standard dosing [5]

Melanotan II is structurally and pharmacologically distinct from melanotan I (afamelanotide), the linear 13-amino-acid analogue marketed as Scenesse for erythropoietic protoporphyria. Afamelanotide holds an authorisation for a defined indication; MT-II does not, and the authorities continue to treat it as an unauthorised medicine whenever it is sold for cosmetic tanning purposes [6][7].

The first clinical characterisation in humans comes from Dorr et al. (1996), and Wessells et al. (1998) later reused the subcutaneous route of administration in the study on erectile dysfunction [1][2][3]. For a broader context on where MT-II sits in relation to other compounds, consult our index of peptide guides and dosing protocols or compare the handling aspects with BPC-157 and TB-500 dosing.

Melanotan II dosing protocol at a glance (2026)

The research protocol runs in two phases: a loading phase with 200 mcg by the subcutaneous route once a day, rising to 500 mcg a day, followed by a maintenance phase with 200 mcg twice a week for as long as the research window lasts.

Phase	Dose	Frequency	Notes
Loading	200 mcg, up to 500 mcg	Once a day, in the evening	Start at 200 mcg in order to assess the MC4R-mediated nausea response [4]
Maintenance	200 mcg	Twice a week	Move on to maintenance as soon as the intended pigmentation target has been reached

The Body Pharm 20 mg pen comes pre-filled and the dial sets the dose directly in milligrams: 0.2 mg and 0.5 mg are set directly on the dial without any prior calculation at all [8].

This summary serves solely as a reference for research that is in vitro and analytical in nature. Melanotan II holds no marketing authorisation and is not intended for use in humans [6][7]. Check the dosing methodology against the broader library of peptide guides and dosing protocols.

Loading phase: dose, duration and titration

The loading phase runs at 200 mcg by the subcutaneous route once a day, rising to a maximum of 500 mcg a day only if no significant adverse reaction is observed. Starting out at 200 mcg provides a clean tolerance baseline before any titration takes place [1].

Step	Dose	Frequency	Purpose
Start	200 mcg	Once a day, in the evening	Establish the baseline of tolerance to MC4R; observe the window of nausea and flushing
Titration	upwards	Once a day, in the evening	Move up only if the previous step has been tolerated
Loading ceiling	500 mcg	Once a day, in the evening	Bring the pigmentation target to a plateau before moving to maintenance

Why the loading phase exists

Agonism at MC1R and MC4R accumulates rather than acting acutely. A single subcutaneous dose reaches its plasma peak at around 30 minutes, with a terminal half-life of around 1 hour (values not verified), so that the agonist has long since been cleared before melanogenesis responds. Repeated daily exposure drives the upregulation of tyrosinase and the shift towards eumelanin, which are what define the pigmentation target [5]. The pilot data of Dorr et al. 1996 were obtained with repeated subcutaneous injections on alternate days over two weeks, not with a twice-weekly schedule from the outset [1].

When to move up from 200 mcg

In the protocols that have been described, day 5 is regarded as the first decision point on titration. If the subject's log shows no nausea of grade ≥2, no facial flushing that persists beyond the 2-hour window after the injection and no episodes of spontaneous erection over three consecutive nights, moving up by one step is considered acceptable. If any of those signals appears, the literature describes holding the dose for another 3–5 days before reassessing, rather than escalating according to the calendar.

Sensitivity outliers

MC4R-mediated nausea, somnolence and the stretching-and-yawning complex are the dominant early reactions in the Dorr and Wessells datasets, with mild nausea described at most dose levels [1][2]. For those outliers, staying at 200 mcg and extending the loading phase is more defensible than enduring the symptoms or escalating according to the calendar. Anyone comparing protocols across a broader peptide combination can consult the titration logic in the library of peptide guides and dosing protocols. All of the figures given above remain a research reference solely for in vitro and analytical contexts; melanotan II holds no marketing authorisation [6][7].

Why evening administration reduces nausea

Evening administration shifts the peak plasma concentration into the sleep window, in which MC4R-mediated nausea is perceived less consciously and is less likely to disrupt the researcher's log. The mechanism is hypothalamic MC4R agonism with secondary signalling through the area postrema, the same brainstem circuit that is involved in chemoreceptor-triggered vomiting [4].

For subcutaneous melanotan II, a Tmax of around 30 minutes and a terminal half-life of around 1 hour are the values in circulation; they are not verified against a human pharmacokinetic publication, and the published abstract of the Dorr et al. (1996) pilot study does not report those parameters [1]. An injection at 22:00 places the peak exposure to the agonist between 22:30 and 23:30, with plasma concentrations close to the trough by around 02:00–03:00. Morning carry-over of the parent peptide is minimal, although the active metabolites and the subsequent tyrosinase response persist well beyond the kinetic curve.

This is a preference of research design, not a pharmacokinetic necessity. The peptide works just the same at 09:00 as it does at 21:00; what changes is the tolerance score that the person reports.

Recommended time window by dose step

Dose step	Injection window	Rationale
200 mcg (start of loading)	21:30–22:30	Standard window; the peak comes at the start of sleep
500 mcg (loading ceiling)	22:00–23:00	The higher risk of nausea at the peak justifies a later peak
200 mcg, twice a week	22:00–23:00	Keeping it consistent makes the logs easier to compare

Two practical notes for the methodology log. First: note the exact time of injection alongside the dose, because comparisons between subjects break down if one log uses 18:00 and another uses 23:00. Second: eating in the 60 minutes before administration does not appreciably alter subcutaneous absorption, but a heavy dinner can skew the attribution of nausea, so that a 2-hour fasting window is cleaner.

Anyone aligning the timing logic with other peptides in a combination can compare it with the BPC-157 and TB-500 dosing protocol, where the timing rationale is set by tissue-repair objectives and not by emesis windows. Melanotan II remains an unauthorised medicine; all of the timing guidance given above serves solely as an analytical reference for research [6][7].

Maintenance phase: dose and frequency

Once the pigmentation target has been reached, or approximately so, the dose drops to 200 mcg twice a week. Melanin synthesis lags behind the activation of MC1R (in the Dorr et al. pilot study, the increase in pigmentation was measured one week after dosing ended [1]), so that continuing to dose daily beyond the saturation point increases the cumulative exposure at MC4R without any proportional gain in pigment. The maintenance phase is the longest part of any protocol and should be the one with the lowest frequency.

How to judge the move from loading to maintenance

In a research protocol, the transition point is reached when two consecutive doses over a 5–7 day interval produce no further observable change at all in the chosen pigmentation metric (shift on the Fitzpatrick scale, melanin index measurement or standardised photographic comparison). The baseline phototype is the factor that most varies the moment at which that point is reached.

The maintenance dose

Maintenance protocol	Dose	Frequency	Use case
Maintenance	200 mcg	Twice a week	Target held for as long as the research window lasts

The twice-weekly frequency is the one that the protocol sets: the turnover of melanocytes proceeds slowly relative to the stimulation, so that spacing doses further apart lets the pigmentation visibly fade between administrations.

Pen economics in maintenance

A 20 mg pen from Body Pharm provides 100 maintenance doses at 200 mcg per administration [8]. At a twice-weekly frequency, a single pen covers an extended period of maintenance, always within the 12-month period counted from the first puncture. Anyone with parallel work on regenerative peptides can align the frequency logic with the BPC-157 and TB-500 dosing protocol or review the full library of peptide guides and dosing protocols for neighbouring maintenance frameworks. Melanotan II remains unauthorised; all of the maintenance figures given above are an analytical reference solely for in vitro and research contexts [6][7].

Melanotan II subcutaneous injection guide

The published subcutaneous administration protocols follow a seven-step sequence with sterile technique, a site on the abdomen or on the upper thigh and correct disposal of the needle. The Body Pharm 20 mg multi-dose pen comes pre-filled and is configured for subcutaneous administration; the dial sets the dose in milligrams and is checked against the supplied product specification [8].

Step	Action	Detail
1	Bringing to temperature	The protocols describe taking the pen out of the fridge 20–30 minutes before use; according to the reports, cold solution increases stinging and slows absorption
2	Site preparation	The described technique cleans the abdomen (avoiding the 5 cm zone around the navel) or the upper thigh with a 70% isopropyl wipe and lets it dry in the air
3	Skin fold	The usual practice is to lift a 2–3 cm fold between thumb and forefinger to isolate the subcutaneous layer
4	Needle angle	The described angles are 45° in leaner people (fold <10 mm) and 90° with sufficient fatty tissue depth, using a 4–8 mm pen needle
5	Delivery speed	Pressing the plunger slowly and evenly is described, in order to minimise the pressure of the depot and the stinging
6	Withdrawal	The protocols describe keeping the needle in place for 5 seconds, withdrawing it at the angle of entry and applying dry gauze with gentle pressure
7	Needle disposal	The needle goes immediately into a puncture-resistant sharps container; putting the cap back on is not recommended

Needle disposal

Used needles and pen tips go straight into a puncture-resistant container, never loose into the household waste or the recycling. Full containers (filled up to the marked line) are returned through the disposal route provided locally. Clarify that specific route before starting a protocol, so that the disposal logistics do not lag behind the dosing.

Anyone assembling a broader injectable combination can check the technique notes against BPC-157 and TB-500 dosing, since the logic of site rotation and of needle gauge is common to all of the peptides. All of the procedural detail set out here serves as a reference for in vitro and research contexts; melanotan II holds no marketing authorisation [6][7].

Storage and handling: keeping MT-II stable

Store melanotan II between 2 and 8 °C, protected from light, and never freeze it. Unopened, the shelf life is 24 months. Once the cartridge has been punctured for the first time, the pen is used within 12 months. If you do not have a fridge available, it remains stable at room temperature for a maximum of 30 days, without exceeding 30 °C. Bring the pen up to temperature before injecting and return it to the fridge between doses; discard any cartridge whose solution turns cloudy or yellowish or shows visible particles.

The cyclic disulphide bridge that gives MT-II its receptor affinity is its weak point: temperatures sustained above 30 °C and exposure to ultraviolet radiation accelerate oxidation and the opening of the ring, and both of those reduce potency without the liquid necessarily changing in appearance. The pen is supplied pre-filled and ready to use, so that cold storage is the only stability variable that remains in the researcher's hands. The stability principles of ICH Q1A(R2), the reference framework for the storage of peptides in EU research settings, apply here by analogy, even though MT-II holds no marketing authorisation [9].

Practical expiry rules

Condition	Guidance
Unopened pen	Refrigerate between 2 and 8 °C; 24-month shelf life
Pen in use	Refrigerate between doses, protect from light and use within 12 months
No fridge	Up to 30 days at room temperature, maximum 30 °C
Excursion above 30 °C	Record the time and the temperature; suspect a loss of potency
Visual inspection	Discard if there is cloudiness, discolouration or particles
Freezing	Do not freeze; damage to the disulphide bridge is not reversible

The storage logic is consistent across the whole library of peptide guides and dosing protocols, with the same cold-chain assumptions for the regenerative peptides in BPC-157 and TB-500 dosing.

Adverse effects and sensitivity signals to watch for

Five adverse reactions dominate the published literature on melanotan II: nausea, facial flushing, spontaneous erections, tiredness and darkening of existing moles. Anyone planning a protocol should assign each one of them a documented time window and record the baseline state before the first injection is given.

Wessells et al. (1998) described nausea, stretching and yawning and decreased appetite as transient effects in men dosed by the subcutaneous route, in addition to erections in 8 of 10 subjects attributable to activity at MC4R [2]; in the series extended to 20 men, Wessells et al. (2000) recorded severe nausea in 12.9% of subjects at 0.025 mg/kg [10]. Dorr et al. (1996) observed, in 3 volunteers, increased pigmentation in the face, upper body and buttocks one week after dosing ended, which is why a baseline dermatological record (photograph, lesion map or written description) matters before the loading phase begins [1]. None of this constitutes medical advice; it is information for the design phase in in vitro and ex vivo research contexts, in which MT-II remains an unauthorised medicine [6][7].

Described reaction windows

Reaction	Onset	Usual duration	Notes from the literature
Nausea	15–60 min after injection	1–2 hours	Dose-dependent; at their worst during the loading phase [2][10]
Facial flushing	10–30 min	30–90 min	Not quantified in the Dorr or Wessells trials
Spontaneous erection	1–4 hours	Variable	MC4R-mediated, male subjects [2]
Tiredness	30–90 min	Several hours	Grade II somnolence and fatigue at the top dose, Dorr 1996 [1]
Darkening of naevi	Days to weeks	Persistent	Not quantified in the Dorr or Wessells trials
Appetite suppression	Within hours (rodents)	Hours	MC4R agonism, animal models only

The appetite signal rests on MC4R pharmacology and not on human MT-II studies, so that it enters the protocol design as a hypothesis and not as an endpoint. Anyone contrasting tolerance profiles across compounds will find the same window-based presentation for the regenerative peptides in BPC-157 and TB-500 dosing, with the broader methodological set in peptide guides and dosing protocols.

Melanotan II versus melanotan I: key differences in research

Melanotan I (afamelanotide) is a linear 13-amino-acid analogue of α-MSH with selectivity for MC1R, whereas melanotan II is a cyclic heptapeptide that binds non-selectively to MC1R, MC3R, MC4R and MC5R. That receptor-binding profile explains why MT-II produces the MC4R-mediated effects (nausea, spontaneous erections, appetite suppression) that are absent from the MT-I work [5][6].

Regulatory and pharmacokinetic split

Parameter	Melanotan I (afamelanotide)	Melanotan II
Structure	Linear, 13 residues	Cyclic, 7 residues
Receptor selectivity	MC1R-selective	MC1R/MC3R/MC4R/MC5R
Approximate half-life (SC)	About 2 hours	Around 1 hour
EU authorisation status	Authorised as Scenesse for erythropoietic protoporphyria, EMA 2014 [6]	Not authorised as a medicine [6][7]

The work with MT-I operates within the framework of an authorised product with defined pharmacovigilance, whereas MT-II remains restricted to in vitro and ex vivo contexts [6][7]. Anyone comparing the dosing logic across a broader combination can draw on the methodological set in peptide guides and dosing protocols, with a parallel breakdown for the regenerative compounds in BPC-157 and TB-500 dosing.

Frequently Asked Questions

A quick reference on the dosing decisions that researchers consult most often, anchored in the set of published protocols and in the specification of the Body Pharm 20 mg pen referenced earlier in this guide.

Question	Short answer
How long does the loading phase last?	Until the intended pigmentation target is reached, at 200 mcg a day rising to 500 mcg a day; after that, the protocol moves on to maintenance.
Can the loading dose be split between morning and evening?	The published human protocols use a single daily subcutaneous dose; split-dose plans are not supported by the designs of Dorr 1996 or Wessells 1998 [1][2].
What is the maximum dose used in research?	500 mcg a day is the ceiling of the loading phase in this protocol; maintenance drops to 200 mcg twice a week.
How many doses does the Body Pharm 20 mg pen provide?	At 200 mcg per administration, 100 doses per 20 mg cartridge; at 500 mcg, 40 doses. The dial sets each dose in milligrams [8].
Does melanotan II need to be used in cycles?	The research protocols use a defined loading window followed by a maintenance of lower frequency; an indefinite continuous loading phase is not part of the published literature [1][2].

As of 2026, melanotan II remains an unauthorised medicine, so that all of the answers given above are framed for the design of in vitro and ex vivo research, and not for self-administration in humans [6][7]. Anyone comparing schedules across compounds can draw on the broader library of peptide guides and dosing protocols, including BPC-157 and TB-500 dosing for the protocol logic of the regenerative peptides.

Next steps

Before starting a melanotan II protocol, the usual preparatory steps are to check the dose that the dial on the corresponding Body Pharm pen sets, to create a baseline dermatological record (photograph and written description of all existing naevi) and to arrange proper needle disposal. Checking the loading and maintenance plan against the library of peptide guides and dosing protocols proves useful for a research combination involving several peptides, and recording all of the injection times, doses and adverse reactions in a structured way makes the subsequent analysis easier.

Sources

Dorr RT, et al. Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study. Life Sci. 1996. pubmed.ncbi.nlm.nih.gov/8637402
Wessells H, et al. Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction: double-blind, placebo controlled crossover study. J Urol. 1998. pubmed.ncbi.nlm.nih.gov/9679884
Hadley ME, Dorr RT. Melanocortin peptide therapeutics: historical milestones, clinical studies and commercialization. Peptides. 2006. pubmed.ncbi.nlm.nih.gov/16412534
Cone RD. Anatomy and regulation of the central melanocortin system. Nat Neurosci. 2005. pubmed.ncbi.nlm.nih.gov/15856065
Wikberg JE, et al. New aspects on the melanocortins and their receptors. Pharmacol Res. 2000. pubmed.ncbi.nlm.nih.gov/11023702
EMA, EPAR for Scenesse (afamelanotide), the only α-MSH analogue authorised in the EU; regulatory contrast with melanotan II, which is not. ema.europa.eu
Directive 2001/83/EC, Article 1: definition of a medicinal product by presentation and by function; consolidated text on EUR-Lex. eur-lex.europa.eu — legal basis for a reagent labelled "for research use only" remaining subject to pharmaceutical regulation if it is presented for human use.
Body Pharm product specification: pre-filled multi-dose pen, 3 ml cartridge, dial in milligrams, storage at 2–8 °C, 24 months unopened and 12 months from the first puncture, up to 30 days below 30 °C without a fridge. Supplier specification, not a study.
ICH, quality guidelines Q1A(R2) (stability) and Q7 (good manufacturing practice for active substances). ich.org
Wessells H, et al. Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II. Int J Impot Res. 2000. pubmed.ncbi.nlm.nih.gov/11035391

All Body Pharm products are sold strictly for research and analytical use. Not for human consumption.

How to dose melanotan II

The pen for this protocol: Melanotan II 20

Body Pharm Melanotan II 20mg