Phosphatidylserine for Dogs: What Day 30 Scores Mean for You
Phosphatidylserine can be a useful supportive nutrient for aging dogs showing early signs of cognitive decline, but it is not a cure. Small clinical studies show measurable improvement in cognitive scores within weeks, so talk to your vet first, rule out other causes, and give any supplement six to eight weeks before judging results. Most dogs do best combining it with diet changes, mental enrichment, and prescribed medication when needed.
TL;DR:
- A study involving ten dogs found DISHAA scores fell from 24 to 15 by day 30; another found improved memory in nine beagles.
- Both canine studies used combination products, so their results cannot establish whether phosphatidylserine alone caused the reported improvements in either study.
- A veterinarian should rule out pain, thyroid or metabolic disease, medication effects, and vision or hearing loss before diagnosing cognitive dysfunction.
- No universal dose exists because trials used combination products; veterinary recommendations should reflect each dog’s weight and health history, not trial amounts.
- Because canine drug interactions are poorly documented, tell your veterinarian about seizure or heart medication, and watch for soft stool or appetite changes.
Table of Contents
- What phosphatidylserine is and how it works in the brain
- What the clinical evidence shows in dogs
- How vets diagnose and track cognitive decline
- Safety, regulatory status, and side effects to watch for
- How to dose phosphatidylserine and what to expect
- Where PetGev Healthy Aging Chews fit into a brain-health plan
- FAQ
- Sources
What phosphatidylserine is and how it works in the brain
Phosphatidylserine is a fat-based compound found in every cell membrane in the body, with especially high concentrations in brain cell membranes. It helps those membranes stay flexible enough for neurons to communicate efficiently, which matters more as a dog ages and brain cell turnover slows.
In practical terms, phosphatidylserine is thought to support several processes at once:
- Helps maintain membrane fluidity so brain cells can send and receive signals normally
- Supports the release of acetylcholine, a neurotransmitter tied to learning and memory
- Shows antioxidant-like activity that may help protect cells from everyday oxidative stress
Most of the dog research does not test phosphatidylserine by itself. It is usually one ingredient in a multinutrient formula alongside antioxidants or other brain-supportive compounds, which makes it hard to credit any single ingredient for the full effect. That distinction matters when you are reading a supplement label.
What the clinical evidence shows in dogs
Two dog-specific studies carry most of the weight behind phosphatidylserine as a cognitive support ingredient, and both used it as part of a combination formula rather than alone.
An open-label study found DISHAA scores dropped significantly at 30 days and 60 days in ten aging dogs given an integrative supplement containing phosphatidylserine, according to a 2023 open-label investigation. Median DISHAA scores fell from 24 at baseline to 15 at 30 days and 14.2 at 60 days, a statistically significant change. That is a meaningful shift in how a dog’s daily behavior and awareness were scored by its owner and vet.
A separate crossover trial in nine aged beagles tested a nutraceutical containing phosphatidylserine, Ginkgo biloba, vitamin E, and pyridoxine against a control condition. Dogs on the supplement performed significantly better on a short-term memory task, a difference that held up statistically.
A few caveats matter here:
- Sample sizes were small, with ten and nine dogs respectively
- Neither study tested phosphatidylserine as a standalone ingredient
- The open-label design in the first study means there was no placebo group for comparison
These results are promising signals, not proof that phosphatidylserine alone reverses cognitive decline. They support its use as one piece of a broader plan rather than a stand-in for veterinary care.
How vets diagnose and track cognitive decline
Before anyone reaches for a supplement, a vet needs to confirm what is actually happening. Cornell’s veterinary college recommends DISHAA, a scoring tool that evaluates Disorientation, Interactions, Sleep-wake cycles, House-soiling, Activity, and Anxiety. Scores fall into mild, moderate, or severe ranges, giving owners and vets a consistent way to track change over time instead of guessing.
Cognitive dysfunction can look identical to several treatable conditions, so a thorough vet visit usually includes:
- Bloodwork (CBC and chemistry panel) to check organ function
- Thyroid testing, since low thyroid function can mimic mental decline
- A pain assessment, because chronic pain often shows up as behavior change
- Vision and hearing checks, since sensory loss is frequently mistaken for confusion
- A full medication review for drugs that might affect alertness or memory
Cornell notes that pain, metabolic disease, and sensory loss all need to be ruled out before cognitive dysfunction syndrome is confirmed.
Pro Tip: Keep a simple weekly log of sleep patterns, house-soiling incidents, and any new confusion or anxiety before your appointment. It gives your vet a real baseline instead of relying on memory.
Safety, regulatory status, and side effects to watch for
Phosphatidylserine has a long track record in food and supplement use. The FDA has reviewed GRAS notices for phosphatidylserine derived from soy, sunflower, and fish lecithin, and previously recognized a qualified health claim stating that consumption “may reduce the risk of dementia in the elderly” in humans, with evidence described as very limited and preliminary. That history points to a generally safe compound for food use rather than a proven therapy.
Canine studies reporting on phosphatidylserine-containing supplements have generally described good tolerability with low rates of adverse events, though vets still recommend watching your dog after starting anything new:
- Mild GI upset, such as softer stool or reduced appetite in the first few days
- Changes in energy or behavior that seem unusual for your dog
- Any signs of allergic reaction, though these are uncommon
If your dog takes other medications, including seizure drugs or heart medication, mention any new supplement to your vet first. Interactions with phosphatidylserine specifically are not well documented in dogs, which is exactly why a quick check-in matters more than skipping it.
How to dose phosphatidylserine and what to expect
Trial dosing gives you a reference point, not a prescription. The aged-beagle trial and the open-label DISHAA study both used capsule-based combination products rather than isolated phosphatidylserine, so there is no universal milligram-per-kilogram number to copy at home. Your vet can recommend a specific product and amount based on your dog’s weight and health history.
What you can plan for:
- Give any new supplement at least 6 to 8 weeks before judging whether it is working
- Track changes using a DISHAA-style score or a simple daily diary instead of relying on memory
- Introduce one new supplement or chew at a time so you can tell what is actually causing a change
A few things to check on the label before buying:
- Whether the product is formulated with veterinary input rather than marketed purely on buzzwords
- The phosphatidylserine source, since soy, sunflower, and fish lecithin versions all appear in the research
- Whether the brand makes claims beyond what the ingredient has actually been shown to do
Pro Tip: Start the clock the day you begin a new supplement, and mark your calendar for a two-month check-in instead of judging results week to week.
Where PetGev Healthy Aging Chews fit into a brain-health plan
A daily chew works best as a foundation you start before problems show up, not a fix you reach for after. Healthy Aging Chews were formulated with Dr. Michael Geist, DVM, DACVIM, board-certified in Small Animal Internal Medicine, and each jar holds 120 soft chews built around 14 ingredients: Cordyceps, Blueberry, Milk Thistle, Antarctic Krill Oil, Salmon Oil, L-Carnitine, Quercetin, Turmeric, Alpha Lipoic Acid, Green Tea Extract, Vitamin E, CoQ10, Astaxanthin, and Black Pepper Extract.
Together those ingredients are formulated to support joints, brain, heart, liver, immunity, skin and coat, and energy, which means one daily routine can replace several separate supplements most owners end up juggling. The daily amount is typically based on body weight.
We built this as a proactive option: something you start while your dog is still doing well, alongside veterinary care, a good diet, exercise, and mental enrichment, not as a replacement for any of them. For owners who want a broader, multi-component approach to long-term wellness, our Dog Longevity Blueprint lays out a more complete plan. Check out Healthy Aging Chews to see if a daily chew fits your dog’s routine.
This article is general information, not a substitute for advice from a qualified doctor. Consult a qualified healthcare professional about your own circumstances before acting on anything here.
FAQ
What are the side effects of phosphatidylserine in dogs?
Reported side effects are generally mild and uncommon, with occasional soft stool or short-term appetite changes noted in canine studies. Watch for any unusual behavior change after starting a new supplement and mention it to your vet.
Is sunflower lecithin okay for dogs?
Sunflower-derived phosphatidylserine has been reviewed by the FDA alongside soy and fish lecithin sources and is generally considered a safe source for food use. Some owners prefer it as a soy-free alternative, though research directly comparing sources in dogs is limited.
What words do dogs hear best?
This question falls outside what the research behind this article covers, since it relates to hearing and language processing rather than phosphatidylserine or cognitive supplements. A veterinary behaviorist is the better resource for training-related sound and word research.
What is the best vitamin to give your dog?
There is no single best vitamin for every dog, since needs depend on age, breed, and health status, and a vet should guide any supplement decision. For senior dogs specifically, cognitive-support research has focused more on compounds like phosphatidylserine, vitamin E, and antioxidants working together than on any one vitamin alone.
How long before phosphatidylserine shows results in dogs?
Clinical studies measured improvement at 30 and 60 days, with DISHAA scores improving significantly by the 30-day mark in one trial. Give any supplement at least six to eight weeks before deciding whether it is helping your dog.
Recommended
PetGev chews are a nutritional supplement for healthy dogs, not a medicine. They are not intended to diagnose, treat, cure, or prevent any disease. Results vary between dogs. Talk to your veterinarian before starting any supplement, especially if your dog is pregnant, nursing, taking medication, or under veterinary care. This article is general information, not veterinary advice.
