@cactusgrammy After that long on a medication like Citalopram, it really can take a long time to titrate off of it. Is there a particular reason you are going to stop it? Your body may have become fairly independent on it.

Has your prescribing doctor given you a suggested schedule?

Here is what I did when I decided to go off of 10mg citalopram several years ago. It was a very slow progression down. First week, all days except one, that day was only a half pill. Next week, 5 days and two half-pills [day 3 and 6]. Then each week I did one half pill more until 7 days of half pills. Next, 6 days of half pills, with 1 day no pill for two weeks. Every two weeks I took another day out. So you can see, it was about 5 months to get off the 10mg pills.
Ginger

At your 20mg dosage, you may want to ask for a 10mg dose, and do the very slow titrate off after you decrease to 10mg over a long course. For me, that is what worked. I kept track on a calendar to be sure it was done safely, and with my doctor's agreement.