How to work out mcg per spray and sprays per dose
A metered nasal-spray bottle delivers a fixed volume each pump. The amount per spray is the total in the bottle divided by the sprays it delivers; your dose is then a whole number of sprays.
- Enter the total in the bottle in mcg or mg from the label or your compounding record.
- Enter the sprays per bottle the metered pump delivers (after priming).
- Enter your prescribed dose to see how many sprays make it up.
- Prime the pump first so each metered spray delivers the full amount, then log your dose.
Worked example: 15 mg in a bottle of 150 sprays
A bottle holding 15 mg of peptide that delivers 150 metered sprays, at a 200 mcg dose:
- Per spray — 15,000 mcg ÷ 150 sprays = 100 mcg/spray.
- Sprays per dose — 200 mcg ÷ 100 mcg/spray = 2 sprays.
- Doses per bottle — 150 sprays ÷ 2 = 75 doses.
Because sprays are whole units, doses that don’t land on an exact number of sprays are approximate — enter your own bottle and dose above.
Frequently asked questions
How do I calculate mcg per spray?
Divide the total amount in the bottle by the number of metered sprays it delivers. For example, 15 mg (15,000 mcg) over 150 sprays is 100 mcg per spray. A 200 mcg dose is then 2 sprays. Enter your own numbers and the tool shows the steps.
Why do I need to prime a nasal spray?
Priming clears air and fills the metering chamber so each pump delivers its full, consistent volume. Without priming, the first sprays can under-deliver, which throws off the mcg-per-spray math. Prime per the product’s instructions.
How many sprays are in my bottle?
The label usually states the number of metered sprays. If it only lists a fill volume, divide the fill volume by the per-spray volume the pump delivers. Use the sprays-per-bottle figure that matches your product.
Is this intranasal calculator medical advice?
No. It is an educational estimation tool that does the arithmetic from your numbers and shows its work; it never recommends a dose. Always follow your licensed provider’s instructions.
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