Is it safe for me to feed Purina Urinary Tract Health formula cat food to both of my cats?

I have two cats. One was just diagnosed with a UTI. =( He’s on antibiotics. I also went and bought a bag of Purina Urinary Tract Health cat food, since I heard it’s good. I read on the website that you’re not supposed to mix it with other types of cat food. In other words, you’re only supposed to feed your cat the Purina Urinary Tract food for maximum effectiveness. So my question is, should I just put down the Purina and take up the regular food? Is it safe for me to do that?

Thanks guys! Any other tips on how to help my kitty feel better are welcome. This is his second UTI. (I think he’s stressed b/c we just moved.)

Welactin Feline Omega-3 Fatty Acids Formula for Cat Health, Skin and Coat Care – 125 Ml

• A rich source of Omega-3 fatty acids derived from salmon and other water fish developed to help support your petÆs skin and coat health and overall wellness.
• Improves your petÆs general appearance, activity level, appetite and alertness.
• Other benefits include renal and nervous system support and improved immune function. Easy to administer, simply add to your petÆs food.

Product Description
INDICATIONS: Welactin Feline Omega-3 fatty acids formula for cat health, skin and coat care: A rich source of Omega-3 fatty acids derived from salmon and other water fish developed to help support your petÆs skin and coat health and overall wellness. Improves your petÆs general appearance, activity level, appetite and alertness. Other benefits include renal and nervous system support and improved immune function. Easy to administer, simply add to your petÆs food…. More >>

Welactin Feline Omega-3 Fatty Acids Formula for Cat Health, Skin and Coat Care – 125 Ml