How many drops of essential oil and/or scents is recommended per use? January 23, 2019 18:08 Updated 2-6 drops is recommended, based on the scent intensity you prefer. Related articles What is difference between the Dohm Classic and Dohm Natural? What is the energy usage for the sound machines? How large of an area does the Purest Sleep Diffuser cover? Are the Sleep Scents safe for use with toddlers and children? Will the Purest Sleep Diffuser work with any essential oil?