What is MK-677 (ibutamoren)?
MK-677 is the original development code for ibutamoren, usually sold as ibutamoren mesylate. The “MK” prefix comes from Merck, where the compound was developed in the 1990s. People searching for MK-677 dosage often assume it is a peptide because it appears on the same supplier lists as ipamorelin, GHRP-6 and sermorelin. It is not. MK-677 is a small, non-peptide molecule classified as a growth hormone secretagogue and a ghrelin receptor agonist.
That difference matters for this site. Peptides such as those in our calculator arrive as freeze-dried powder in a sealed vial and have to be dissolved before use. Ibutamoren is chemically stable as a finished oral product, so it is sold as MK-677 capsules, tablets, or a flavored MK 677 liquid in a dropper bottle. The strength is fixed by the manufacturer and printed on the label. This page describes those product forms and the numbers on them. It makes no claims about effects in people.
Can you mix MK-677 with BAC water?
This is one of the most common questions we see, usually typed as “mk 677 bac water.” The short answer: there is nothing to mix. Bacteriostatic water is used to reconstitute lyophilized (freeze-dried) injectable powders. MK-677 is not sold that way. Capsules and tablets are finished solid products, and MK 677 liquid is already a solution when you buy it.
Because nothing is being reconstituted, there is no vial mg to divide by a water volume, no concentration to calculate and no U-100 syringe-unit math. That is why the calculator on this page is shown greyed out. Adding BAC water to a capsule’s contents or to an oral liquid would not turn it into anything the syringe calculator can describe; it would only dilute a product away from the strength on its label. If you want the background on what bacteriostatic water is actually for, see what BAC water is and how it works.
MK-677 dosage: what this page can and can’t tell you
Every compound page on this site takes the same stance: we do the math on an amount you already have, and we never set, suggest or check an amount. For injectable peptides that math is converting mg into syringe units. For MK-677 dosage there is no conversion step to perform, because the amount per capsule, tablet or mL is already stated on the product.
So this page will not give you an MK-677 dosage, a schedule, a cycle length or a frequency, and nothing here should be read that way. Those are questions for the product labeling and a qualified professional. What we can do is explain how the label strength is written, so the number on the bottle is not misread.
Reading MK-677 capsules and liquid labels
Oral products state strength per unit of product, not per vial. The common formats are:
- Capsules or tablets: written as mg per capsule or mg per tablet. The number applies to one capsule; the bottle total is that figure times the count.
- Oral liquid: written as mg per mL. The amount in a given volume is the mg per mL figure multiplied by the mL measured.
- Powder sold by weight: some suppliers list bulk ibutamoren powder in grams. The label weight is the total powder, not a per-serving amount.
Two pure unit facts help with all three: 1 mg = 1,000 mcg, and 1 g = 1,000 mg. If a label mixes units, convert both figures to the same unit before comparing. Also check whether the label names ibutamoren or ibutamoren mesylate, because the salt form adds weight to the listed figure. Different brands can state this differently, so compare labels rather than assuming two products match.
MK-677 vs peptide secretagogues
MK-677 is often grouped with injectable peptides that are also called growth hormone secretagogues, such as ipamorelin, GHRP-2 and GHRP-6. The grouping describes a shared receptor class, not a shared product form. Those peptides are sold as freeze-dried vials, so they do use BAC water and syringe-unit math, and each has its own calculator page with a mixing chart.
Ibutamoren is the odd one out: a small molecule sold in oral forms. If you are comparing it with a peptide on the same shelf, keep the units separate. A peptide page reports micrograms per syringe unit after mixing; an MK-677 label reports mg per capsule or per mL as sold. The two numbers are not interchangeable and cannot be entered into the same calculator.
Is MK-677 FDA-approved?
No. Ibutamoren is not an FDA-approved drug, and there is no approved MK-677 product with labeled strengths or directions to compare against. Capsules, tablets and liquids sold online are generally labeled for research use. It was studied clinically after its development, but it was never approved as a medicine.
Because it is a secretagogue and not a peptide vial, MK-677 sits outside the reconstitution tools on this site. For compounds that are sold as freeze-dried vials and do need BAC water math, browse the peptide library, where each page has a mixing chart and a preselected calculator.
MK-677 (Ibutamoren) FAQ
Do you mix MK-677 with BAC water?
No. MK-677 is sold as capsules, tablets or an oral liquid, not as a freeze-dried vial, so there is nothing to reconstitute. Bacteriostatic water is used for lyophilized injectable powders.
Is MK-677 a peptide?
No. MK-677, also called ibutamoren, is a small non-peptide molecule. It is grouped with some peptides because it is classified as a growth hormone secretagogue, but its structure and product form are different.
Does this page give an MK-677 dosage?
No. This site does not set or suggest amounts, schedules or cycles. The strength per capsule, tablet or mL is on the product label, and dosing questions belong with a qualified professional.
Why is the calculator greyed out on this page?
The calculator converts a vial’s mg and the BAC water you add into syringe units. MK-677 has no vial or water volume, so that math does not apply.
What is the difference between MK-677 capsules and MK 677 liquid?
Capsules state strength in mg per capsule, while liquids state it in mg per mL. Read the unit on the label carefully before comparing two products.