Finally — a Lysine Formula Built for Cats with FHV-1
Immune Support
gut defense
respiratory health
Your cat acts unbothered. Their immune system? Not so much. L-Lysine is the one amino acid cats can't make on their own — and without it, a super common feline virus turns into chronic sneezing, goopy eyes, and general sad cat vibes. One scoop over their food and they're back to judging you from across the room.
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FHV-1 shows up in the same patterns. If your cat has any of these, L-Lysine may help.
If any of these sound familiar, your cat's immune system is likely fighting feline herpesvirus (FHV-1) — the most common cause of recurring eye and respiratory symptoms in cats. There is no cure for FHV-1, but the symptoms are absolutely manageable. L-Lysine is the most widely recommended intervention, and Daybreak delivers it at the dose that matters — 900mg — combined with three supporting ingredients most formulas don't include.
Feline herpesvirus (FHV-1) is a lifelong virus. Once a cat has it, it stays dormant in the body and flares up when the immune system is under stress. The virus needs an amino acid called arginine to replicate. L-Lysine competes with arginine, making it harder for the virus to multiply during a flare-up. This is the mechanism vets have leveraged for decades.
But FHV-1 doesn't affect only one system. It triggers airway inflammation, stresses the gut, and drains immune resources. That's why Daybreak combines 900mg L-Lysine with Krill Omega-3(to reduce inflammation in airways and around the eyes) and FOS Prebiotic (to support the gut microbiome that regulates immune function). One formula. The full picture.
Most lysine supplements contain one ingredient. Daybreak contains four — because FHV-1 affects more than one system in your cat's body.
An essential amino acid that competes with arginine to limit FHV-1 replication.
At 900mg per serving, this is one of the highest-dose formulas available without a prescription. Most competing products contain 500mg.
Fructooligosaccharide feeds beneficial gut bacteria, which regulate immune function. Particularly important for cats who have been on antibiotics — which deplete the gut flora that keep immunity strong.
Provides EPA/DHA Omega-3 to reduce inflammation in the airways, joints, and around the eyes — critical during FHV-1 flare-ups where secondary inflammation compounds symptoms. More bioavailable than plant-based Omega-3.
N,N-Dimethylglycine supports immune modulation and energy metabolism. Helps the immune system respond appropriately without over-triggering the inflammatory response behind FHV-1 flare-up symptoms.
Real ingredients
MAnufactured IN THE USA
NO FILLERS OR JUNK
Non gmo
"The stuff the vet wanted to give me had 400mg of L-Lysine less and was $50 more." — Verified Amazon Purchase
Your cat begins eating the powder in wet food. Palatability confirmed. No visible change yet — completely normal.
Many owners report first improvements in eye discharge and sneezing. Immune support has begun building.
Consistent daily use builds up. Most cats show meaningful symptom reduction. Energy often improves noticeably.
Maintenance phase. Daily use suppresses flare-up frequency — many cats go months without a visible episode.
Join thousands of cat owners who've made Daybreak L-Lysine part of their daily routine. 60 servings. One scoop. Results most owners notice within the first week.
