Question 1

How much glucosamine should I give my dog by weight?

Accepted Answer

The evidence-based glucosamine dose for dogs is 20 mg/kg/day for maintenance and 40 mg/kg/day for therapeutic use in dogs with active joint issues. For a 30 lb (14 kg) dog: maintenance is 280 mg/day, therapeutic is 560 mg/day. For a 60 lb (27 kg) dog: maintenance is 540 mg/day, therapeutic is 1,080 mg/day. Most commercial products contain 500–1,500 mg per chew — always check the label against your dog's calculated dose.

Question 2

How much omega-3 fish oil should I give my dog daily?

Accepted Answer

The evidence-based omega-3 dose for dogs is 40 mg/kg EPA+DHA daily for maintenance and 75 mg/kg EPA+DHA for therapeutic anti-inflammatory effect. For a 20 lb (9 kg) dog: 360–675 mg EPA+DHA/day. For a 50 lb (23 kg) dog: 920–1,725 mg EPA+DHA/day. Use the total EPA+DHA number from the label, not the total fish oil volume. Triglyceride-form fish oil has about 70% higher bioavailability than ethyl ester form.

Question 3

What is the melatonin dose for dogs by weight?

Accepted Answer

Melatonin dosing for dogs by weight: dogs under 10 lbs — 1 mg; 10–25 lbs — 1.5 mg; 25–100 lbs — 3 mg; over 100 lbs — 3–6 mg. Give 30–60 minutes before a stressor (fireworks, travel, vet visit) or at bedtime for sleep regulation. Critical: NEVER use human melatonin products that contain xylitol — xylitol is highly toxic to dogs. Check the ingredient list for xylitol before giving any human melatonin product.

Question 4

Can I give my dog multiple supplements at the same time?

Accepted Answer

Most common dog supplements are safe to combine, but some combinations require timing or dose adjustments: (1) Fish oil + blood thinners (warfarin) — potential additive anticoagulant effect, monitor with vet; (2) Probiotics + antibiotics — give at least 2 hours apart; (3) SAMe — must be given on an empty stomach, 1 hour before food; (4) Melatonin + benzodiazepines — increased sedation risk. Run your specific combination through an interaction checker before combining, especially if your dog is on prescription medications.

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