Dosage - How long is a 2.5 ml bottle supposed to last when you use 1 drop in each eye per day?
Question posted by marmal56 on 2 Aug 2013
Last updated on 7 July 2021 by DrakeRPH
6 Answers
The number of drops per ml of any medication varies depending on the viscosity and density of the solution. Also some manufacturers overfill the bottles to provide extra doses. The prescriber info for Latanoprost solution by Sandoz states that each bottle of 2.5ml contains 24 drops per ml, which is 60 drops The brand name Xalatan by Pfizer is overfilled and contains more than 100 drops per 2.5ml bottle. Studies have been done to analyze the drops per ml, quantity per bottle and cost of use for all manufacturers of latanoprost. Patients will argue that they receive much lower than 20-24 drops per ml. However, a general rule of thumb is 20 drops per ml unless specific info is provided by the manufacturer.
25 days.
I think it's 2.5 ml in total solution 4 ml, thus 80 drops.
Oops, it's 4ml bottle, 2.5 solution. Literature does say 80 drops though, so worth checking with manufacturer.
There are 20 drops per milliliter. If you have the 2.5ml bottle, that's 50 drops. If you're only using 2 drops per day, it will be a 25 day supply. I'm a CPhT, so I know what I'm talking about.
1ml=16drops so 2.5ml is about 37 drops so a 2.5ml will only last about 2 weeks and 3 days.
You should check the Sandoz pdf drug description that claims the 80 drops per 2.5 ml bottle.
More or less 2.5ml of eyedrops, with the usage details you are giving, should last you 15 days.
So where do they get the answer that says..the 2.5ml has 90 drops in it??? Please explain..thanks..
Sandoz claims that in the 2.5 ml bottle, there are 80 drops which is nearly 3 months. At one drop a day, the solution should last 80 days NOT 15 days.
If you want the correct answer from a pharmacist. Here it is. 1 ml is 20 drops. So 2.5 is 50 drops. If it's once a day in each eye, then 25 days. The other answers are incorrect. Hope that helps.
Related topics
eye conditions, latanoprost, dosage
Further information
- Latanoprost uses and safety info
- Latanoprost prescribing info & package insert (for Health Professionals)
- Side effects of Latanoprost (detailed)
Similar questions
Search for questions
Still looking for answers? Try searching for what you seek or ask your own question.