Is a 10 mg extra strong dual action melatonin tablet (Adrien Gagnon) divisible? I would like to decrease the dosage as I woke up still feeling the effects of melatonin the next morning after taking the tablet.

No, the 10 mg melatonin double action extra-strength tablets from Adrien Gagnon are not meant to be split. It is recommended to use 3 mg tablets that are available to swallow in most pharmacies.