How to take Trintellix. Read the Medication Guide provided by your pharmacist before you start taking Trintellix and each time you get a refill. Take this medication by mouth with or without food as directed by your doctor, usually once daily. The dosage is based on your medical condition, response to treatment and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).