How We Test and Review Pet Health Products

Our Promise

At Pet Health Authority we deliver independent, evidence-driven reviews so you can make confident choices for your pet’s health. Our recommendations are based on clinical relevance, laboratory testing, and real-world use — not on advertiser influence.

Who We Are

Lead reviewer Dr. Renee Parker is a board-focused veterinary nutritionist with 14 years working in animal health, clinical nutrition, and pet wellness. Dr. Parker evaluates supplements, veterinary products, and nutrition formulations using clinical experience from primary care and specialty practice, plus laboratory partnerships for objective testing. Her emphasis is on ingredient quality, safety standards, and evidence-based effectiveness so your pets receive care backed by science and veterinary practice.

Pet Health Authority pairs Dr. Parker’s clinical judgement with a multidisciplinary team of veterinary technicians, analytical chemists, and in-home field testers. We design tests to mimic everyday pet care scenarios — from administering a joint chew to monitoring a dietary change — and we publish methods and findings to keep our reviews transparent and useful to pet owners and veterinary professionals alike.

How We Select Products to Review

We identify products for review using a structured research pipeline that balances market relevance with potential impact on pet health. Selection is driven by data, clinical need, and owner concerns.

• Market signals: Amazon Best Sellers, category sales trends, veterinary distributor data, and repeat-purchase patterns to prioritize widely used products.
• Owner feedback: Analysis of thousands of customer reviews, reported side effects, and common service queries to highlight products with real-world relevance.
• Regulatory and safety flags: FDA Center for Veterinary Medicine (CVM) alerts, recalls, and consumer complaint trends to prioritize safety investigations.
• Clinical importance: Products that target major health issues (joint support, GI health, renal diets, skin/coat, feline taurine supplementation, etc.) or contain trending ingredients (EPA/DHA ratios, probiotics with specified strains, CBD formulations, glucosamine types) are fast-tracked for review.
• Manufacturer transparency: Brands that provide full ingredient disclosure, certificates of analysis (COAs), and third-party test results are prioritized for deeper evaluation.

Our Testing Criteria

Ingredient Sourcing, Identity & Purity

We verify that active ingredients are described accurately (e.g., glucosamine HCl vs. sulfate, EPA/DHA amounts in mg), check source species for allergens or contaminants (fish oil source, bovine vs. poultry), and screen for prohibited ingredients like xylitol. Where possible we send samples to third‑party labs for purity assays and heavy metal screens (ICP‑MS) and require Certificates of Analysis for each lot.

Clinical Evidence & Mechanism of Action

We evaluate whether claims are supported by peer‑reviewed studies or controlled trials in dogs or cats, and whether endpoints are clinically meaningful (improved mobility scores, reduced pruritus, stabilized renal values, or validated stool consistency scales). Products relying solely on in vitro data, extrapolated human studies, or vague “proprietary blends” score lower unless supported by species-specific clinical evidence.

Safety Profile & Tolerability

Safety testing includes review of adverse event reports, potential drug–nutrient interactions (e.g., anticoagulants with omega‑3s), species‑specific contraindications (like added vitamin D for cats/dogs), and lab screening for microbial contamination. We monitor short‑term and subacute tolerability in in‑home trials and review veterinary case reports to detect gastrointestinal upset, allergic reactions, or metabolic effects.

Dosing Accuracy & Bioavailability

We confirm that label dosage recommendations match measured active ingredient amounts via assays such as HPLC or LC‑MS when applicable, and test formulations for expected release characteristics (chews vs capsules). For nutrients where form matters (e.g., chelated minerals, methylated B‑vitamins, or omega‑3 triglyceride vs ethyl ester forms), we evaluate bioavailability evidence and adjust scoring accordingly.

Palatability & Owner Compliance

Practical use matters: we run in‑home palatability trials across multiple breeds and life stages to measure acceptance rates, administration ease (pills, chews, liquids), and owner burden over a typical 7–14 day period. Products that pets consistently refuse or that require complex administration score lower for real‑world effectiveness.

Manufacturing Controls & Third‑Party Verification

We assess GMP adherence, third‑party certifications (NASC membership for supplements, independent lab COAs), and lot‑to‑lot consistency through stability testing. Packaging, expiration dating, and storage conditions (refrigeration requirements, light‑sensitive formulations) are evaluated because they materially affect potency and safety in everyday use.

Our Rating System

We use a 1–5 star rating scale to summarize a product’s overall suitability for typical pet health goals. Ratings are based on weighted criteria: clinical evidence (40%), safety (25%), formulation & ingredient quality (15%), palatability/compliance (10%), and manufacturing transparency (10%).

• 5 stars — Excellent: Strong species‑specific clinical support, lab-verified formulation, with high palatability and excellent safety profile.
• 4 stars — Very Good: Good clinical evidence and safety; minor limitations such as limited palatability data or single‑study support.
• 3 stars — Fair: Mixed or limited evidence and/or minor safety or formulation concerns; may be appropriate in some situations with veterinary guidance.
• 2 stars — Poor: Weak evidence or notable safety/quality concerns; use only under veterinary supervision, if at all.
• 1 star — Avoid: Fails safety checks, lacks transparency, or contains ingredients with documented harm or mislabeling.

Affiliate Disclosure

Some links on Pet Health Authority are affiliate links. If you buy through those links we may earn a small commission at no extra cost to you. Affiliate relationships do not influence our reviews: Dr. Renee Parker and our editorial team test and rate products independently, and our recommendations are based solely on the criteria described on this page.

Last Updated

February 23, 2026