Ah, nuts!
Happy memories of pistachios, olives and raki on Greek islands in my youth. Ok, not the raki.
I was surprised to see that pistachios have more carbohydrate than peanuts, which some people avoid because it's hard to eat only sufficiently few to not have much effect on blood sugars. Pistachios seem to have 13.6g carbs per 100g, while peanuts have 13.3g. Not much in it, but more than walnuts, almonds, pecans and macadamias, for example, which are all nearer 5g carbs per 100g.
Having said all that, 25g of pistachios (shelled) will only have 3.4g carbs so it won't kill you. Try testing your blood sugar an hour or 2 afterwards and see how it effects you.
All the best,
fergusc