There is no universal replacement schedule that applies to every professional lash adhesive.
Start with the manufacturer's directions for the product you are using. Then track what happens after you open it.
Write Down the Opening Date
This tiny habit can make troubleshooting much easier.
Without a date, artists often say a bottle has been open for “a few weeks.” When retention changes, guessing whether that means three weeks or six weeks is not very useful.
Writing the date directly on the bottle removes the guesswork.
Watch for Changes
Get familiar with how a fresh bottle behaves. Notice its consistency, drop behaviour, working characteristics, and your normal retention results.
If those characteristics begin changing, investigate.
Do not judge the adhesive from one unusual appointment alone. Look at the product, your environment, application, and whether the same issue is appearing across multiple clients.
A change in performance does not automatically prove the adhesive is responsible, but bottle age becomes one useful part of your investigation.
The Takeaway
Know the manufacturer's recommendations, date every bottle when you open it, and learn what normal performance looks like.
The more accurately you track your products, the less often you have to troubleshoot from memory.
Learn next: How Should Lash Adhesive Be Stored? Why Does Lash Adhesive Get Stringy? How Can I Improve Lash Retention?