How a 5 kg cat reacts to two flavored chips
The main concern here is the seasoning blend rather than the potato itself—onion or garlic powder in some chips can cause mild red blood cell damage with repeated exposure, but two chips won't reach that threshold. Your cat's vomiting suggests her stomach is already reacting to the salt and fat content. This isn't inherently dangerous at this quantity, but it's uncomfortable for her.
Watch closely for any changes in gum color (pale or yellowish gums would be concerning) or breathing rate over the next six hours. The vomiting window for this amount usually closes by the 4-hour mark—if she keeps retching past that, something else might be irritating her stomach lining beyond the chips.
Why timing matters with flavorings
Artificial flavors and preservatives like disodium inosinate often cause drooling or lip-licking within 90 minutes, while gastrointestinal signs take slightly longer. Since it's been an hour already, you're right in the peak observation window. Don't be alarmed by one or two more vomits—the stomach empties in waves.
What would push this into vet territory? Multiple vomiting episodes (more than three in an hour), any blood in the vomit, or if she starts pressing her abdomen against cool surfaces. Right now, withholding food for another two hours before offering a teaspoon of plain boiled chicken is reasonable.
Hydration needs after salty snacks
A 5 kg cat needs about 200 ml of water daily under normal circumstances—those two chips likely made her thirstier. Provide multiple water stations with wide, shallow bowls (cats dislike deep bowls that touch their whiskers). Add an ice cube to encourage lapping if she's not drinking voluntarily.
Check for dehydration by gently pinching the skin at her shoulders—it should snap back instantly. If the tent persists for even a second, or if her saliva feels sticky when you rub it between your fingers, she's tipping into mild dehydration. This is when subcutaneous fluids might help, but at this chip quantity, oral rehydration should suffice.
When to expect normal behavior again
Most cats bounce back within six hours after minor chip ingestion. You'll know she's improving when she grooms herself normally (cats stop grooming when nauseated) and shows interest in surroundings rather than hiding. Don't worry if she skips one meal—their digestive systems handle intermittent fasting well.
If she's still lethargic when the 8-hour mark hits, that's your cue to check in with the vet. Bring the chip bag if possible—the ingredient list helps them rule out less common toxins like xylitol in some 'sweet chili' flavors. But with what you've described, odds are she'll be stealing your snacks again by tomorrow.
The full verdict, portion guidance and serving notes are collected on the Chips / crisps food facts page.