CBD Dosage for Dogs: Vet-Reviewed Chart by Weight

You bought a bottle of CBD oil for your dog. Now you're staring at the dropper, doing math in your head, and second-guessing every number. The bottle says "500 mg" but doesn't tell you what that means for a 45-pound Lab with arthritis. The internet says "start low and go slow." But how low? How slow?

The problem with most CBD dosage for dogs guides is that they give you a single number and call it done. Real dosing is condition-specific, weight-dependent, and should be grounded in published veterinary research, not brand marketing.

This guide gives you three things: a weight-based CBD oil dosage chart built from peer-reviewed studies, the clinical reasoning behind each protocol, and an interactive dosing calculator that does the math for you.

CBD Dosing Chart for Dogs by Weight

The chart below uses the three most-cited veterinary CBD protocols. All doses are per administration, given twice daily (every 12 hours) unless noted otherwise.

How to read this chart: Find your dog's weight, then look at the column for the condition you're addressing. These are per-dose amounts given twice daily. For a custom calculation based on your dog's exact weight, use our CBD dosing calculator.

Where These Numbers Come From

Every number in the chart above is derived from one of three published veterinary studies. No brand dosing guides. No anecdotal recommendations. Here is the research:

Arthritis and Pain: 2 mg/kg Twice Daily

The foundation study for CBD dosing in dogs is Gamble et al. (2018), published in Frontiers in Veterinary Science. Cornell University researchers enrolled 22 dogs with confirmed osteoarthritis in a randomized, placebo-controlled, double-blind crossover trial.

Dogs received 2 mg/kg of CBD oil twice daily for 4 weeks. The results:

• Significant decrease in pain scores (CBPI and Hudson activity scores)
• Increased comfort and activity levels observed by owners and veterinary assessors
• No clinically significant side effects
• Mild elevation in the liver enzyme ALP in some dogs, without clinical concern

This is the most-cited CBD dosing study in veterinary medicine. The 2 mg/kg twice daily protocol has become the standard reference point for pain management in dogs. For the full clinical trial breakdown including the Baylor confirmation study, see our CBD for dogs with arthritis guide.

Seizures: 2.5 mg/kg Twice Daily

McGrath et al. (2019) at Colorado State University conducted a randomized, placebo-controlled trial of 26 dogs with intractable idiopathic epilepsy. Dogs received 2.5 mg/kg of CBD twice daily in addition to their existing anti-seizure medications.

Key findings:

• 89% of dogs in the CBD group had a reduction in seizure frequency
• Mean seizure frequency decreased significantly compared to placebo
• CBD was given as an add-on to existing medications, not a replacement
• Mild ALP elevations were again noted in some dogs

This is the only published RCT for CBD and seizures in dogs. The 2.5 mg/kg protocol is specific to epilepsy as an adjunctive treatment. Do not discontinue existing anti-seizure medication without your veterinarian's explicit guidance. For the full trial breakdown including drug interactions and ALP monitoring, see our CBD for dogs with seizures guide. If your dog has cancer and you're considering CBD for quality-of-life support, see our CBD for dogs with cancer guide for oncology-specific dosing and chemotherapy interaction risks.

Anxiety: 1.4 mg/kg Single Dose

Hunt et al. (2023) tested a single dose of 4 mg/kg THC-free CBD in dogs experiencing separation stress and car travel. The study found significant reductions in cortisol levels and stress-related behaviors compared to placebo.

For regular dosing, we use the 1.4 mg/kg twice daily range based on available pharmacokinetic data and the clinical consensus that has emerged since the Hunt results. For situational anxiety (fireworks, thunderstorms, vet visits), a single larger dose of 2–4 mg/kg administered 60–90 minutes before the event may be more appropriate. See our fireworks anxiety protocol for event-specific timing or our thunderstorm anxiety guide for the year-round storm protocol.

General Wellness: 0.5–1 mg/kg Twice Daily

No single study defines a "wellness" dose. This range represents the lower bound of therapeutic protocols and is used by veterinary practitioners for dogs without a specific clinical condition who may benefit from CBD's anti-inflammatory and anxiolytic properties. Start at 0.5 mg/kg and increase only if needed.

How to Actually Measure a Dose

The chart tells you how many milligrams to give. But the bottle gives you a dropper measured in milliliters. Here is how to bridge that gap.

Step 1: Find Your Product's Concentration

Look at the bottle (or, better, the COA). You need two numbers: total CBD in the bottle and total volume.

• A 30 mL bottle containing 500 mg CBD = 16.7 mg per mL
• A 30 mL bottle containing 1,000 mg CBD = 33.3 mg per mL
• A 60 mL bottle containing 1,500 mg CBD = 25 mg per mL

Most droppers hold 1 mL when fully drawn. A quarter dropper = 0.25 mL. This is the math that determines whether your dog gets an appropriate dose or four times that amount.

Step 2: Calculate Your Dropper Amount

Divide the dose your dog needs (from the chart) by the product concentration.

Example: A 50-pound dog with arthritis needs approximately 45 mg per dose. Using a 1,000 mg / 30 mL product (33.3 mg/mL): 45 ÷ 33.3 = 1.35 mL, or just over one full dropper.

If you prefer not to do the math, our dosing calculator handles this automatically.

Step 3: Administer with Food

CBD is lipophilic: fat increases absorption. A pharmacokinetic study by Zgair et al. (2017) demonstrated that oral cannabinoid bioavailability increases substantially when taken with a fatty meal. Give CBD oil directly onto food or mix with a small amount of peanut butter, wet food, or a high-fat treat.

The Starting Protocol

Regardless of condition, follow this approach:

Why ramp up? Even though published safety data shows CBD is well-tolerated at doses far higher than therapeutic levels (Gamble et al. (2018) reported no significant adverse effects at 2 mg/kg), every dog responds individually. Ramping up lets you identify the lowest effective dose for your dog and catch any sensitivity early.

Factors That Affect Your Dog's Dose

Body Weight

CBD dosing is weight-based (mg per kg of body weight). A 15-pound Dachshund and a 90-pound German Shepherd need very different absolute amounts of CBD, even for the same condition.

Product Type

CBD oils (tinctures) typically have the highest bioavailability of oral CBD products. Treats and chews pass through more of the digestive process, which may reduce absorption. If switching from oil to treats, you may need a slightly higher dose to achieve the same effect. For a breakdown of oral product formats, see our CBD vs hemp oil guide. For COA-verified product picks, see our best CBD treats for dogs comparison or our CBD calming treats guide for anxiety-specific formulations.

Spectrum Type

Full-spectrum products contain CBD plus minor cannabinoids (CBG, CBN, CBC) and trace THC (<0.3%). The "entourage effect" hypothesis suggests these compounds may work synergistically, potentially allowing a lower CBD dose. Broad-spectrum removes THC while retaining other cannabinoids. CBD isolate is pure CBD only. Most published dog studies used either isolate or broad-spectrum formulations.

Food and Timing

As noted above, administering CBD with a fatty meal increases absorption. Peak blood levels are reached approximately 1.5–2 hours after oral administration. For situational use (fireworks, vet visits), dose 60–90 minutes before the event for maximum plasma concentration at the time of the stressor.

Age and Liver Function

Senior dogs with reduced liver function may metabolize CBD more slowly, leading to higher effective blood levels. If your dog is elderly or has diagnosed liver disease, start at 25% of the target dose rather than 50% and increase more gradually. Baseline bloodwork before starting CBD is advisable for any dog over 10 years old.

Signs You've Given Too Much

CBD has a wide safety margin. Vaughn et al. (2024) studied tolerability at 2 and 4 mg/kg every 12 hours and confirmed good tolerability across both dose levels. But individual dogs can still show sensitivity. Watch for:

• Excessive sedation: sleeping significantly more than normal, difficulty waking
• Unsteady gait: wobbly or disoriented movement (distinct from joint pain)
• GI distress: vomiting or diarrhea, especially in the first 48 hours
• Significant appetite drop: refusing meals for more than 24 hours

If you observe any of these: skip the next dose, then resume at 50% of the previous dose. If symptoms persist after reducing, discontinue and consult your veterinarian. None of these effects are dangerous in isolation, but they indicate the dose is too high for your individual dog. For a deeper dive into safety thresholds and what to do in an emergency, see our guide on whether dogs can overdose on CBD. For the complete safety picture across 8 published studies, see Is CBD safe for dogs?

Drug Interactions

CBD inhibits cytochrome P450 (CYP450) liver enzymes, the same pathway that metabolizes many common veterinary drugs. This is not theoretical; it is the same mechanism behind grapefruit-drug interactions in humans.

If your dog takes any of these medications, consult your veterinarian before adding CBD:

• Phenobarbital: CBD may increase blood levels. The McGrath seizure study specifically noted ALP elevation in dogs taking both CBD and anti-seizure drugs.
• NSAIDs (carprofen, meloxicam, deracoxib): both CBD and NSAIDs reduce inflammation through different mechanisms. Combining them requires vet oversight to avoid compounding liver effects.
• Gabapentin: CBD may potentiate sedative effects. Dose reduction of one or both may be needed.
• Corticosteroids (prednisone, prednisolone): overlapping anti-inflammatory mechanisms. Monitor for excessive immunosuppression.
• Sedatives and anesthetics: always disclose CBD use before any surgical procedure.

This list is not exhaustive. The CYP450 pathway metabolizes hundreds of drugs. If your dog is on any chronic medication, a conversation with your vet about CBD interactions is not optional. It is essential.

A Note on Cats and Horses

This chart is for dogs. Cats and horses require different dosing protocols.

Cats lack efficient glucuronidation, a liver enzyme pathway that dogs use to metabolize cannabinoids. This means CBD stays in a cat's system longer and at higher effective concentrations. Feline doses should be roughly 50% of the equivalent dog dose. We cover this in detail in our CBD oil for cats guide, including a cat-specific dosing table.

Horses require weight-adjusted protocols with large absolute doses. Equine-specific CBD research is limited. See our CBD for horses guide for what's currently known (when available).

Our dosing calculator handles all three species.

Getting the dose right comes down to three numbers: your dog's weight, the condition, and your product's concentration. Once you have those, the research-backed protocols here do the rest, and our broader library of CBD for pets guides extends the same evidence-first approach to cats, horses, and specific conditions when you need it.

Frequently Asked Questions

How much CBD should I give my dog?

It depends on the condition. For general wellness, start at 0.5–1 mg/kg twice daily. For pain and arthritis, the Gamble et al. (2018) protocol is 2 mg/kg twice daily. For seizures, McGrath et al. (2019) used 2.5 mg/kg twice daily as an add-on to existing medication. Always start at 50% of the target dose for the first week. Use our weight-based dosing calculator for your dog's exact amount.

Can you give a dog too much CBD?

CBD has a wide safety margin in dogs. Vaughn et al. (2024) confirmed tolerability at 4 mg/kg every 12 hours, and no published study has reported serious toxicity from CBD alone. However, too high a dose can cause excessive sedation, GI upset, or unsteady gait. If you see these signs, reduce the dose by 50%. The greater risk is from THC contamination in mislabeled products. Always verify THC content via a third-party COA.

How long does CBD take to work in dogs?

CBD reaches peak blood levels in dogs approximately 1.5–2 hours after oral administration. For situational anxiety (fireworks, vet visits), dose 60–90 minutes beforehand. For chronic conditions like arthritis, consistent daily dosing for 2–4 weeks is typically needed before you see meaningful behavioral changes. The Gamble et al. study assessed outcomes at 4 weeks.

Should I give CBD to my dog once or twice a day?

Twice daily (every 12 hours). All three major published protocols (Gamble for arthritis, McGrath for seizures, and clinical consensus for anxiety) use a twice-daily administration schedule. This maintains more consistent blood levels than once-daily dosing. The exception is situational anxiety, where a single dose 60–90 minutes before the stressor may be appropriate.

Can I give my dog CBD with other medications?

CBD inhibits cytochrome P450 liver enzymes, which metabolize many common veterinary drugs including phenobarbital, NSAIDs, and gabapentin. This can alter blood levels of these medications. CBD is not contraindicated with most drugs, but the interaction requires veterinary oversight, and your vet may need to adjust doses of existing medications when adding CBD.