To answer your first question, they both contain the same amount of active ingredient (Pravastatin 40 mg), but there is a difference in the inactive ingredients which are listed.

The first light green tablet with imprint PB on one side and 8 on the other is manufactured by Accord (NDC 16729-010), and also contains:

- Croscarmellose Sodium
- Lactose Monohydrate
- Magnesium Oxide
- Magnesium Stearate
- Microcrystalline Cellulose
- D&C Yellow No. 10
- FD&C Blue No. 1
- Povidone

The second green pill with imprint APO on one side and PRA over 40 on the other side is manufactured by Apotex (NDC 60505-0170), and also contains:

- Croscarmellose Sodium
- Lactose Monohydrate
- Magnesium Stearate
- Microcrystalline Cellulose
- FD&C Blue No. 1
- Ferric Oxide Yellow

I personally cannot say whether there would be a difference in side effects between the two, as I am not prescribed this medication. But hopefully there should not be a noticeable difference since they are both technically the same drug. I hope this helps!