Brief Answer:
Different brands have different inactive ingredients.

Detailed Answer:
Hello and welcome,

Different formulations of the same active ingredient can have different effects.

In this case, the active ingredient is zolpidem, which is in both products.

But the inactive ingredients and how the medicine is formulated can differ between the products.

For example, I can only tolerate brand name antihistamine Zyrtec but cannot tolerate any of the generic versions of the same medicine. In theory, they should be identical, but generic versions do not always get it quite like the original brand name product. And different manufacturers can use different inactive ingredients (binders, colors etc).

Sometimes it is hard to explain to insurance companies that you can't tolerate a cheaper product and need the brand name. But for those who are sensitive to a particular product, that is the case.

I hope this information helps. Please let me know if I can provide further information or clarification.

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