Almost every digestive enzyme is safe to take.
If you're really concerned, just take a 100% papain (which is the active ingredient in paw paw).
Most digestive enzymes will contain:
- Betaine HCL (hydrochloric acid) - which is what your stomach naturally produces
- Protease - to break down protein
- Lipase - to break down fat
- Cellulase - to break down cellulose
- Amalyse - to break down carbohydrates
+ a few other ingredients to help in digestion.
I think your best bet to ask a pharmacist for advise!