Pet supplements / best for immune & respiratory
Best immune & respiratory supplements, ranked.
L-lysine and immune-support supplements for feline herpesvirus and respiratory health, where the evidence is often thinner than the marketing.
Ranked by PetScored composite (evidence quality 30%, active dose 25%, ingredient clarity 15%, safety and manufacturing 15%, value 15%). This ranking is our opinion under a published rubric, not veterinary advice. A product can rank below a peer because its headline active is weakly evidenced or its dose is hidden, even when it is well made.
- VetriScience Vetri-Lysine Plus for Cats
A fully disclosed, NASC-sealed L-lysine chew for cats at a studied dose, from a maker that owns its facility and frames lysine as a mechanism rather than a cure; like every lysine product the catch is the same, the controlled evidence is against lysine for feline herpesvirus, so good execution and a fair price cannot lift it past the evidence ceiling.
Catssoft chew7.1Mixed - Vetoquinol Enisyl-F L-Lysine Oral Paste
A well-made, NASC-sealed, properly dosed L-lysine paste from an owner-operator manufacturer, but the controlled evidence is against lysine for feline herpesvirus, which lands it in Limited; to its credit the label stays restrained and does not over-claim a cure.
Catsliquid6.4Limited
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