Switching back to pregabalin from venlafaxine?

Hi, Matthew!
Venlafaxine has a very short half life and usually stays in your system for about 2-3 days. I'd err on the side of caution and give it at least that long.
Depending on how long you've been taking venlafaxine and at what dosage stopping the medication, especially if you stop cold turkey, can cause some very unpleasant discontinuation symptoms.
I'd recommend you talk with your doctor before changing your medications.

I’m currently taking the two pregabalin 600mg and venlafaxine 225mg plus my other medication & I’ve no issues..