For an emergency repair on an inside pocket, fold the torn edge under and secure it with safety pins or staples.
If a patch (exterior) pocket gives way, attach it with double-sided sticky tape. (Don't put anything in the pocket until you can make repairs.) Or, if you can fold under the loose section, fasten it from the inside with safety pins.
For a permanent repair, instead of stitching, insert iron-on tape between the two seam allowances of an inside pocket or between a garment and its patch pocket; press with a warm dry iron to fix the tape in place.
