Tools
Methylene blue dosage calculator
By An NayalLast reviewed 2 sources
Methylene blue is sold as a liquid, so the hard part is the math: turning a percent strength into milligrams, and a dose into a volume or a drop count. Enter your bottle and Pepteca does the conversion.
For your target dose
1mL
≈ 20 drops (approximate)
Concentration
10 mg/mL
Per drop (approx)
0.5 mg
Unit conversion only. This does not tell you what dose to take, and low- dose oral methylene blue use is community practice, not clinically established. Only pharmaceutical (USP) grade is fit for human use, and methylene blue is dangerous with many antidepressants. Verify with a licensed provider.
Save this dose to the Pepteca tracker (early access)
The tracker is on the way. Leave your email and we will tell you when it opens, so you can save setups like this one and log each dose. Email only, unsubscribe anytime.
Worked example
The calculator opens with a 1% solution, a 10 mg target and a dropper that gives 20 drops per mL. Here is what it does with those numbers.
- Concentration: 1% x 10 = 10 mg/mL. The tool shows 10 mg/mL.
- Volume for the target: 10 mg / 10 mg/mL = 1 mL. The big number reads 1 mL.
- Drops for that volume: 1 mL x 20 drops/mL = 20 drops. The tool shows about 20 drops, marked approximate.
- Amount in one drop: 10 mg/mL / 20 drops/mL = 0.5 mg. The "per drop" box shows 0.5 mg.
Tap 0.5% instead and keep the same 10 mg target. The concentration halves to 5 mg/mL, so the volume doubles to 2 mL, which is about 40 drops, and each drop holds about 0.25 mg. Tap 2% and it goes the other way: 20 mg/mL, 0.5 mL, about 10 drops, and about 1 mg per drop. The same target in milligrams can be a very different volume depending on the bottle, which is why the strength on the label is the first thing to get right.
How the math works
A weight/volume percent is definitional: 1% means 1 g per 100 mL, which is 10 mg per mL. The calculator multiplies the percent by 10.
mg/mL = percent x 10
From there, the volume for a dose is the dose divided by the concentration, and drops are that volume times how many drops your dropper puts in a millilitre.
mL = target dose (mg) / mg/mL
drops = mL x drops per mL
mg per drop = mg/mL / drops per mL
The drops-per-mL field defaults to 20, a common figure for a standard dropper, but drop size varies, so the drop numbers are estimates and the mL figure is the one to trust. If you clear that field or enter 0, the calculator falls back to 20. The strength and the target dose must both be above zero, or the result panel asks you to fill them in instead of showing a number.
On screen, the volume is rounded to three decimal places, the drop count to one, the concentration to two and the mg per drop to three. Trailing zeros are dropped, so 1.000 mL shows as 1. The math runs on the unrounded values, so rounding never stacks from one line to the next.
Sources
- [1]Methylene Blue Injection, USP 1% - FDA label (DailyMed)labelConfirms a 1% methylene blue solution equals 10 mg/mL.
- [2]PROVAYBLUE (methylene blue) injection - FDA label (DailyMed)labelThe FDA-approved injectable is a 0.5% solution (5 mg/mL), anchoring the percent-to-concentration math.
Questions people ask
How many mg per mL is a 1% methylene blue solution?
10 mg/mL. A weight/volume percent means grams per 100 mL, so 1% is 1 g in 100 mL, which is 10 mg in each mL. The FDA label for methylene blue injection 1% states the same figure. By the same rule, 0.5% is 5 mg/mL and 2% is 20 mg/mL.
How do I convert mg of methylene blue to mL?
Divide the mg by the concentration in mg/mL. For a 1% solution (10 mg/mL), 10 mg is 1 mL and 5 mg is 0.5 mL. For a 0.5% solution (5 mg/mL), the same 10 mg is 2 mL.
How much methylene blue is in one drop?
It depends on the strength and your dropper. At the calculator's default of 20 drops per mL, one drop of a 1% solution holds about 0.5 mg, one drop of 0.5% about 0.25 mg, and one drop of 2% about 1 mg. A dropper that gives more drops per mL gives less per drop.
Are the drop counts exact?
No. Drop size is not standardized and changes with the dropper, the angle and the liquid. The mg/mL and mL figures are exact arithmetic; the drop figures are estimates. When precision matters, measure by volume with a syringe or a marked dropper.
Pepteca is for education and information only. It does not provide medical advice, diagnosis, or treatment, and its calculators perform unit math only. Always verify with a licensed provider before starting, changing, or stopping any protocol. Many peptides are not approved for human use and may be regulated differently where you live.