Pet supplements we rate Limited, and why.

A proprietary-blend multivitamin (weak wellness evidence) that was named in a February 2025 Class I recall; the blend cap, the recall penalty, and the low evidence tier land it firmly in Limited.

NASC-sealed and heavily marketed, but a proprietary blend hides the per-active doses and the cost per day is high, so it lands in Limited.

The studied De Simone (former VSL#3) multi-strain formulation, NASC-sealed, but it discloses only a combined 112.5 billion CFU rather than per-strain amounts, so under our rules it is a proprietary blend (Active Dose capped) and at over a dollar a day it lands in Limited.

A seven-strain probiotic from a batch-testing maker at the studied strain set, well priced; the multi-strain evidence is modest and per-strain CFU is hidden behind a proprietary blend, so it lands Limited.

A 7-strain probiotic that names its strains but discloses only a combined 7.5 billion CFU, so we cannot confirm an effective per-strain dose and the Active Dose score is capped; the marketing also reaches past the acute-diarrhea evidence into allergy, immune, and behavior claims. Well made and inexpensive per day, but the hidden per-strain dose and claim breadth land it low.

The classic petroleum-jelly hairball gel, NASC-sealed and clearly labeled, but it has no controlled efficacy trial in cats; a peer-reviewed review notes no study has evaluated the common hairball-prevention strategies. The lubricant mechanism is plausible and low-risk, but the 'eliminate and prevent' claim runs ahead of the evidence, so it scores at the floor. Fiber, not lubricant gels, is the hairball approach with actual trial support.

A four-strain probiotic with prebiotics, NASC-sealed and well priced, but the combined 6 billion CFU hides each strain's dose behind a proprietary blend, so it lands Limited.

A petroleum-free hairball gel that licks off the paw, built on vegetable oils rather than petrolatum, with every active disclosed and an NASC seal. The catch is that petroleum-free is a sourcing story, not an efficacy one: a vegetable-oil lubricant gel rests on the same absent evidence as the traditional petroleum kind, because a peer-reviewed review found none of the commonly recommended hairball-prevention strategies have been tested in cats. The label stays modest, claiming to lubricate and minimize shedding rather than to eliminate hairballs, which is why it edges just above the petrolatum gel on honesty while landing in the same low band. Fiber is the only hairball approach with trial support.

An NASC-sealed, fully-disclosed feline multivitamin from an owned cGMP facility; well made and cheap, but a general-wellness multivitamin for a healthy cat on a complete diet has weak evidence, which is what holds it down.

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.