L-Lysine 900mg + Krill Omega-3 + FOS Prebiotic + DMG — because your cat's immune health is more than one ingredient. No soy. No corn. Made in the USA.
900+ verified cat owners recommend this formula
4.7 Stars | 900+ Reviews | 1M+ Units Sold
Is Your Cat Dealing With Any of These?
Eye discharge or goopy eyes
Sneezing or congestion
Low energy or lethargy
Recurring infections
Joint stiffness (senior cats)
Digestive sensitivity
Adopted from a shelter
Symptoms that keep coming back
All of these can trace back to one underlying factor: a cat immune system that needs more support than food alone provides. Daybreak Nutrition L-Lysine is a multi-ingredient formula designed to address immune health at four levels — viral suppression, inflammation, gut health, and energy metabolism.
01
L-Lysine 900mg — Immune Support at the Source
An essential amino acid that supports immune function and helps manage feline herpesvirus (FHV-1) — the most common underlying cause of recurring eye, respiratory, and immune symptoms in cats. At 900mg per serving, this is clinical-range supplementation in a powder your cat can eat daily.
02
Krill Omega-3 — Reduces Systemic Inflammation
A natural source of Omega-3 EPA/DHA that reduces systemic inflammation. Supports joint comfort, coat health, respiratory ease, and cardiovascular function. Krill Omega-3 is more bioavailable than fish oil or plant-based alternatives — your cat absorbs more of what they need.
03
FOS Prebiotic — A Healthy Gut Is a Stronger Immune System
Fructooligosaccharide — a prebiotic fiber that feeds beneficial gut bacteria. A healthy gut microbiome is foundational to strong immune function. Particularly important for cats who have been through antibiotic treatment, which depletes the beneficial bacteria your cat's immune system depends on.
04
DMG — Immune Modulation and Energy Metabolism
N,N-Dimethylglycine supports immune modulation and energy metabolism. Helps cats maintain healthy immune responses and energy levels — particularly valuable for cats with chronic conditions, senior cats, or immunocompromised cats. This is the ingredient that makes Daybreak genuinely different from every other lysine product on the market.
Plus: Natural Chicken Broth Powder for palatability. No soy. No corn. No artificial additives. Just what your cat needs — nothing it doesn't.
Cats with recurring URI or sneezing - Supports respiratory immune function and reduces airway inflammation
Rescue, foster, and shelter cats - Immune support for high-stress transitions and post-antibiotic recovery
Senior cats - Multi-system support for immune, joint, coat, and digestive health as cats age
Any cat whose owner wants proactive immune support - Daily immune maintenance — stay ahead of health issues before they start
L-Lysine for Cats
900mg L-Lysine + Krill + Prebiotic + DMG. One scoop over their food. That's it.
Regular price
$19.95
Regular price
Sale price
$19.95
Immune Support
gut defense
respiratory health
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Trusted by Thousands of Cat Owners
Why Daybreak — Not the Brand at Your Vet's Office
Leading pet supplements
L-Lysine per serving
500mg
900mg
Additional active ingredients
lysine only
Krill + fos prebiotic + dmg
Made in the USA
Third-party tested
No soy / no corn / no additives
Price
$20–50 more for less
affordable
When will I see results?
DAYS 1–3
Your cat begins eating the powder in wet food. Palatability confirmed. No visible change yet — completely normal.
DAYS 4–7
Many owners report first improvements in eye discharge and sneezing. Immune support has begun building.
WEEKS 2–4
Consistent daily use builds up. Most cats show meaningful symptom reduction. Energy often improves noticeably.
MONTH 2+
Maintenance phase. Daily use suppresses flare-up frequency — many cats go months without a visible episode.
Frequently Asked Questions
How much L-Lysine does my cat actually need?
- Vets typically recommend 500-1,000mg per day for cats with FHV-1. Daybreak delivers 900mg per scoop - right in the therapeutic range, without a prescription. Use 1/2 scoop for cats under 6 months, 1 full scoop for cats over 6 months.
Is it safe to use everyday long-term?
- Yes. L-Lysine is an amino acid - a natural building block found in protein. It is safe for daily, on going use. Most veterinarians recommend continuous supplementation for cats with FHV-1 rather than cycling on and off, as consistent levels produce better viral suppression.
My cat is a picky eater - will they actually eat this?
- This is the most common concern and the most common positive surprise. The natural chicken broth powder and krill meal create a savoury flavor most cats accept readily. Mix it into wet food for best results. Over 60% of our reviewers specifically mention their picky cats eating this without issue.
How is this different from the lysine my vet sells?
- Most vet-dispensed lysine supplements contain 500mg per serving. Daybreak delivers 900mg plus Krill Omega-3 and FOS Prebiotic that the vet’s brand doesn’t include. As one reviewer noted: “This brand has 400mg more than the leading product and is still cheaper”
What if symptoms don’t improve after two weeks?
- L-Lysine is a supplement - it supports immune health, it does not replace veterinary care. If your cat’s symptoms are severe or worsening after two weeks, please see your vet. For many cats, combining vet guidance with daily L-Lysine supplementation produces the best outcomes.
Why is the powder clumping? How do I prevent it?
- Keep the silica desiccant packet inside the jar at all times and store in a cool, dry place. The krill meal ingredient can absorb moisture if the packet is removed. With the packet in place, the powder stays free-flowing through the full 60 servings.
Why Customers Choose Daybreak
900+ verified customers. Made in the USA. 30-day guarantee.
More L-Lysine than any vet-dispensed brand
900mg per serving — clinical range, no prescription needed
The only formula with 4 active immune ingredients
Lysine + Krill + Prebiotic + DMG in one scoop
Made in the USA. 30-day money-back guarantee.
If it's not right for your cat, we'll refund you — no questions asked.