Your dog came home with a bottle of prednisone and a label saying something like "give one and a half tablets once daily." You looked up a dosage chart to sanity-check it, found one in seconds, and the chart says your dog should be getting a quarter of that.
So now you have what feels like a maths problem and is actually a category problem. The chart is not wrong, exactly — it answers a different question than your vet answered. Prednisone does not have a dose in dogs. It has two, they differ fourfold, and the chart that circulates online is built from the lower one.
Below: both dose ranges as veterinary references give them, charted by weight; the arithmetic behind the popular charts; why prednisone and prednisolone are one drug in a dog and two in a cat; why your vet may have said "every other day"; and the one thing never to do, which is stop the drug because your dog looks better.
Key takeaways
- There are two dose ranges, not one. Merck: "The anti-inflammatory dosage of prednisolone is 0.5–1 mg/kg, PO, every 24 hours in dogs," while "the immunosuppressive dosage of prednisolone is 2.2 mg/kg, PO, every 24 hours in dogs."¹
- The chart you find online is an anti-inflammatory chart. Work its weight bands back to mg/kg and every one lands on 0.55 mg/kg — the floor of the lower range. No widely published chart gives the immunosuppressive dose by weight.⁶
- In a dog, prednisone and prednisolone are interchangeable; in a cat they are not. VCA: prednisone "is quickly converted to prednisolone in the liver," but "cats and horses are unable to complete this conversion."³
- Stopping abruptly is the real danger, not the dose. Merck: abrupt discontinuation "may lead to an Addisonian-like crisis," and "in severe cases, circulatory shock and death may result."²
What is the prednisone dosage for dogs by weight?
It depends on which of two jobs the drug is doing, and the difference is not a rounding error. The Merck Veterinary Manual gives both figures in the same paragraph: "The anti-inflammatory dosage of prednisolone is 0.5–1 mg/kg, PO, every 24 hours in dogs (severe cases may require 2 mg/kg, PO, every 24 hours)," and "the immunosuppressive dosage of prednisolone is 2.2 mg/kg, PO, every 24 hours in dogs (up to 6.6 mg/kg, PO, every 24 hours may be required in severe disease)."¹
At the standard figures that is a four-fold gap; at the extremes of each range — 0.5 against 6.6 mg/kg — more than thirteen-fold. Same drug, same dog, same tablet, and a correct prescription anywhere across that span depending on whether your vet is calming an itch or suppressing an immune system attacking the dog's own red blood cells.
The table below converts both ranges to total milligrams per day, plus the maintenance target Merck names for long courses: "reduced to the lowest possible maintenance dosage (ideally 0.25 mg/kg, PO, every 48–72 hours or lower in dogs)."¹ These are reference ranges derived by arithmetic from the mg/kg figures, not a dose to give your dog.
| Weight | Anti-inflammatory 0.5–1 mg/kg daily | Immunosuppressive 2.2 mg/kg daily | Long-course maintenance 0.25 mg/kg every 48–72 h |
|---|---|---|---|
| 5 lb (2.3 kg) | 1.1–2.3 mg | 5.0 mg | 0.6 mg |
| 10 lb (4.5 kg) | 2.3–4.5 mg | 10.0 mg | 1.1 mg |
| 20 lb (9.1 kg) | 4.5–9.1 mg | 20.0 mg | 2.3 mg |
| 30 lb (13.6 kg) | 6.8–13.6 mg | 29.9 mg | 3.4 mg |
| 40 lb (18.1 kg) | 9.1–18.1 mg | 39.9 mg | 4.5 mg |
| 50 lb (22.7 kg) | 11.3–22.7 mg | 49.9 mg | 5.7 mg |
| 60 lb (27.2 kg) | 13.6–27.2 mg | 59.9 mg | 6.8 mg |
| 80 lb (36.3 kg) | 18.1–36.3 mg | 79.8 mg | 9.1 mg |
| 100 lb (45.4 kg) | 22.7–45.4 mg | 99.8 mg | 11.3 mg |
One shortcut makes the gap memorable. A kilogram is 2.2046 lb, so Merck's immunosuppressive figure of 2.2 mg/kg works out to 0.998 mg per pound — near enough exactly 1 mg per pound of body weight. The anti-inflammatory range, by the same conversion, is 0.23–0.45 mg per pound.
Why does every prednisone chart online show the same low numbers?
Because they are the same chart, and it is an anti-inflammatory one. The version that recurs reads: 5–20 lb, 1.25–5 mg; 20–40 lb, 5–10 mg; 40–80 lb, 10–20 mg; 80–160 lb, 20–40 mg — printed identically by SingleCare and by A-Z Animals, among others.⁶
Divide the top of each band by the top of its weight range and the bands dissolve. Five milligrams at 20 lb is 0.25 mg per pound. Ten at 40 lb, twenty at 80 lb, forty at 160 lb — 0.25 mg per pound, every time. Not four weight bands: one straight line, 0.25 mg/lb, which converts to 0.55 mg/kg, the very bottom of Merck's anti-inflammatory range. The familiar "2.5 mg per 10 lb" rule of thumb is the same number reached another way.
To be fair, several pages say so somewhere. SingleCare notes these doses "fall within the anti-inflammatory range," and A-Z Animals calls its table "only a reflection of baseline starting doses for mild conditions."⁶ But the qualification sits beside the chart rather than in it — and on some pages, not at all: one dosage-chart site offers "1 mg per kg (0.45 mg per lb)" as its standard reference while listing immune-mediated disease among the conditions it covers.⁶ That is under half Merck's immunosuppressive figure.
So the gap is not that the charts are wrong. It is that none of them charts the other dose at all. You can find the anti-inflammatory dose for your dog's exact weight in seconds, and the immunosuppressive one nowhere in that form. The owner of a 20 lb dog correctly prescribed 20 mg a day — 2.2 mg/kg, straight off Merck's figure — checks the only chart on offer and reads it as four times too much. That is the wrong conclusion to reach alone, at home, about a drug whose dose is what holds the disease down.
Is prednisone the same thing as prednisolone?
In a dog, near enough that veterinary references publish a single dose range for both. VCA explains why: prednisone "is quickly converted to prednisolone in the liver, so they are considered bioequivalent (equally absorbed)."³ Prednisone is the inactive prodrug, prednisolone the active drug, and a healthy canine liver makes that swap efficiently enough to rarely change a prescription.
It is not universally true, and the exception is the single most useful thing on this page for multi-pet households. VCA continues: "some animals, including cats and horses, are unable to complete this conversion, so prednisolone must be administered directly."³ A Cornell crossover trial measured the size of that gap in eleven healthy cats: a single 2 mg/kg oral dose of prednisolone "produced significantly higher plasma prednisolone concentration (~4-fold higher AUC) compared to prednisone."⁵ Four times the active drug from the same milligram figure.
So the leftover half-bottle of your dog's prednisone is not a cat medicine, even scaled down, and in a dog with liver disease the conversion step is worth asking about. One practical note from VCA: "Give this medication with food," and for a once-daily dose, "give it in the morning to dogs."³
Most prednisone use in pets is also off-label: VCA notes its use "to treat inflammation, immune-mediated disease, Addison's disease, and neoplasia is often off label (extra label)."³ That is normal practice, not a red flag — but it explains why no FDA client information sheet carries a tidy weight chart for this drug, and why calculator sites filled the vacuum.
Why would a vet prescribe prednisone every other day?
To buy the drug's effect while leaving the adrenal glands a window to work in. Merck is direct: "All anti-inflammatory glucocorticoid drugs in use today inhibit the HPAA" — the hypothalamic-pituitary-adrenal axis that tells the body to make its own cortisol.² Suppress that signal round the clock for long enough and the glands stop being asked to do anything.
Spacing the doses is the standard mitigation. "The adverse effects of longterm (>2 weeks) glucocorticoid treatment can be diminished using an alternate-day treatment regimen," Merck notes, and on the maintenance dosage it is firmer still: "Maintenance doses must be administered ≥48 hours apart to minimize adrenal suppression and chronic adverse effects."¹² Prednisone is intermediate-acting, with a duration of roughly 24 hours, which is what makes a 48-hour interval leave a genuine gap rather than just a thinner blanket.²
The shape of a long course follows from that. Merck describes the higher dosage as "administered for an induction period of 5–7 days and then reduced to the lowest possible maintenance dosage."¹ Hit it hard, briefly; step down; stretch the interval; find the floor.
An alternate-day schedule is also the easiest rhythm in the house to get wrong. Daily is a habit; alternate-day is a calculation, and one "did you give it last night?" turns a Tuesday into a double dose or a four-day gap. Our guide to keeping a shared dosing rota straight covers that.
What happens if you stop prednisone suddenly?
At worst your dog can die of it, and the risk rises the longer the course has run. VCA states the rule without hedging: "Do not stop this medication abruptly; taper it slowly to avoid complications."³ Merck supplies the mechanism and the consequence: "Longterm suppression of the HPAA may cause adrenal gland atrophy and resultant iatrogenic secondary hypoadrenocorticism. In affected animals, abrupt discontinuation of glucocorticoid treatment may lead to an Addisonian-like crisis characterized by lethargy, weakness, vomiting, and diarrhea. In severe cases, circulatory shock and death may result."²
Read plainly: a dog on long-term prednisone has outsourced its cortisol supply to a tablet. Take the tablet away at once and nothing is held in reserve. The dog does not have too little prednisone — it has none at all, at a moment when every tissue still expects some.
Which is why the most dangerous moment of a prednisone course is the one that feels like good news: the itch has gone, the dog is bright, tablets are left in the bottle, and stopping seems kind. It is also why a taper is a prescription in its own right, not a suggestion.
The other half of the long-course picture is what the drug does while it is working. "Longterm administration may lead to iatrogenic Cushing syndrome, characterized by polyuria, polydipsia, bilaterally symmetric alopecia, increased susceptibility to infection, muscle atrophy, and redistribution of body fat," Merck records.² That is a steroid-induced copy of a disease dogs also get naturally, and the reason a vet pushes for the lowest dose that holds.
Which prednisone side effects are normal, and which need a vet?
Thirst, appetite and urination are expected at any dose; the rest sort by course length. VCA splits them so: "At any dose, prednisone/prednisolone may cause increased drinking, increased urination, and increased appetite," while "at higher doses and during long-term use" the list extends to vomiting, diarrhoea, panting, gastrointestinal ulceration, pot belly, weight gain, muscle wasting, liver and lipid elevations and diabetes.³
| What you see | How to read it | What to do |
|---|---|---|
| Drinking, urinating and eating much more³ | Expected at any dose; usually tracks how high the dose is | Log it and plan for more toilet breaks; raise it if it does not ease as the dose comes down |
| Panting and mild behaviour change³ | Listed at higher doses and on longer courses | Mention at the next check; note which days and at what dose |
| Pot belly, muscle wasting, symmetrical hair loss, repeat infections² | The iatrogenic Cushing pattern of long-term use | Needs a review of dose and interval — book it rather than waiting |
| Vomiting, black or bloody stool, sudden appetite loss³ | Possible gastrointestinal ulceration | Call the same day; far more likely if an NSAID is also on board |
| Lethargy, weakness, vomiting and diarrhoea after a dose is skipped or stopped² | The Addisonian-crisis pattern | Urgent — contact your vet or an emergency hospital immediately |
VCA also names the monitoring that goes with a long course: bloodwork, urinalysis, blood sugar and ACTH testing, with extra caution in pets who already have diabetes, infections or kidney disease.³ A steroid that raises blood sugar, in a dog already at risk of diabetes, is a combination your vet wants numbers on — our guide to the early signs of diabetes in dogs covers what that looks like at home.
Can a dog take prednisone and an NSAID at the same time?
No, and this is the one combination to refuse even if both bottles came from the same clinic. The FDA's owner guidance is a single sentence: "Never give aspirin or corticosteroids (such as prednisone) along with an NSAID to your dog."⁴
The reason is additive damage to the gut lining. Both classes independently raise the risk of gastrointestinal ulceration, and VCA lists that ulceration among prednisone's own higher-dose effects.³ Stack a corticosteroid on an NSAID and you are not running two moderate risks side by side; you are running one considerably larger one.
This catches people out during a switch: a dog on arthritis medication flares up with something itchy, gets a short prednisone course, and the old tablets stay in the morning bowl because nobody said otherwise. Our guide to which arthritis drugs can and cannot be combined covers the wash-out question, and the same boundary applies to anything from the human medicine cabinet — as our guide to aspirin dosing and safety in dogs sets out.
Does the weight on the chart mean your dog's actual weight?
Probably, but the research raises the question rather than settling it. Every figure here is milligrams per kilogram of body weight, which assumes two 60 lb dogs are the same dosing problem — one lean and muscled, one carrying fifteen pounds of fat.
The Cornell group looked at that in cats and it mattered. Over-conditioned cats reached plasma drug concentrations roughly two-fold higher than normal-conditioned cats on the same mg/kg dose, which the authors suggested "might explain their perceived increased risk for glucocorticoid associated side effects (hepatic lipidosis, diabetes mellitus)." Their conclusion recommended "consideration of lean body mass or ideal body weight for dosing practices."⁵
That was a feline study in eleven cats, and reading it as established canine practice would be wrong — dogs convert prednisone differently, and no equivalent canine figure is quoted here because none was found. But it reframes what the number on the scales is for: if your dog is substantially overweight, body condition is worth raising alongside the weight when a long course is planned. Our guide to body condition scoring and where your dog actually sits covers how vets assess it.
Meanwhile what most often goes wrong with prednisone is not the milligrams. It is the sequence, and a dose chart holds none of it. What to have written down before the recheck:
- Each dose and its strength — "one tablet" means different things in week one and week four.
- Which days were dose days, once an alternate-day rhythm starts.¹
- Water intake, judged the same rough way daily rather than from memory.
- Appetite and weight, on the same scales.²
- Anything from the urgent row above, with the date it started.
Veterinary medical disclaimer: SteadyTails is a logging and coordination tool, not a substitute for veterinary care. Nothing on this page is a diagnosis, a prescription or a dosing instruction. Prednisone is prescription-only, and every figure quoted or derived here is a reference range recorded in a veterinary source, not an amount to give your dog — the only dose that governs your dog is the one on your prescription label. Never start, stop, pause, lower, raise or double a dose on your own judgement, and never give a dog an NSAID alongside prednisone. If your dog becomes lethargic or weak, vomits repeatedly, passes black or bloody stool, or collapses — particularly after a dose has been missed or a course stopped — contact your veterinarian or an emergency animal hospital straight away; in the US, ASPCA Animal Poison Control is available around the clock on 888-426-4435.
"Was yesterday a dose day, or was that Tuesday?"
Tapers are where households lose track — a dose that steps down mid-week, an alternate-day rhythm nobody can hold in their head, a thirst change in week three that only shows up if someone wrote week one down. SteadyTails keeps every dose, skip, weight and symptom note on one timeline the whole household writes to. Coming soon to iOS and Android.
Join the SteadyTails waitlist →References
- Merck Veterinary Manual. Hormonal Treatment for Integumentary Disease in Animals — "The anti-inflammatory dosage of prednisolone is 0.5–1 mg/kg, PO, every 24 hours in dogs (severe cases may require 2 mg/kg, PO, every 24 hours), 1–2 mg/kg, PO, every 24 hours in cats". "This dosage is administered for an induction period of 5–7 days and then reduced to the lowest possible maintenance dosage (ideally 0.25 mg/kg, PO, every 48–72 hours or lower in dogs and 0.4–1 mg/kg every 48–72 hours in horses)." "Maintenance doses must be administered ≥48 hours apart to minimize adrenal suppression and chronic adverse effects." "The immunosuppressive dosage of prednisolone is 2.2 mg/kg, PO, every 24 hours in dogs (up to 6.6 mg/kg, PO, every 24 hours may be required in severe disease), 4.4 mg/kg, PO, every 24 hours in cats". merckvetmanual.com Retrieved 2026-10-01.
- Merck Veterinary Manual. Corticosteroids in Animals — "All anti-inflammatory glucocorticoid drugs in use today inhibit the HPAA". "The adverse effects of longterm (>2 weeks) glucocorticoid treatment can be diminished using an alternate-day treatment regimen." "Longterm administration may lead to iatrogenic Cushing syndrome, characterized by polyuria, polydipsia, bilaterally symmetric alopecia, increased susceptibility to infection, muscle atrophy, and redistribution of body fat." "Longterm suppression of the HPAA may cause adrenal gland atrophy and resultant iatrogenic secondary hypoadrenocorticism." "abrupt discontinuation of glucocorticoid treatment may lead to an Addisonian-like crisis characterized by lethargy, weakness, vomiting, and diarrhea." "In severe cases, circulatory shock and death may result." Glucocorticoids "may also slow wound healing." Potency table: prednisone duration of action "I = intermediate (~24 hours)". merckvetmanual.com Retrieved 2026-10-01.
- VCA Animal Hospitals. Prednisolone/Prednisone — "Prednisone is quickly converted to prednisolone in the liver, so they are considered bioequivalent (equally absorbed). However, some animals, including cats and horses, are unable to complete this conversion, so prednisolone must be administered directly." "While some products are labeled for use in some animals with certain conditions, its use in cats, dogs, horses, small mammals, birds, and reptiles to treat inflammation, immune-mediated disease, Addison's disease, and neoplasia is often off label (extra label)." "Give this medication with food. If your pet is on a once daily dose, give it in the morning to dogs and horses, and give it in the evening to cats, if possible." "At any dose, prednisone/prednisolone may cause increased drinking, increased urination, and increased appetite" — with vomiting, diarrhea, behavioral changes, panting, gastrointestinal ulceration, haircoat changes, pot belly, weight gain, weakness, liver and lipid elevations, aggressive behavior, muscle wasting, low energy and diabetes at higher doses and on long-term use. "Do not stop this medication abruptly; taper it slowly to avoid complications." Monitoring by bloodwork, urinalysis, blood sugar and ACTH testing, with caution in pets with diabetes, infections or kidney disease. vcahospitals.com Retrieved 2026-10-01.
- U.S. Food and Drug Administration. Controlling Pain and Inflammation in Your Dog with Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) — "Never give aspirin or corticosteroids (such as prednisone) along with an NSAID to your dog." "If you think your dog is having a side effect to an NSAID, STOP giving the drug and call your veterinarian immediately!" Owners are advised to tell the veterinarian about "all drugs and other products (such as a flea and tick product or a joint supplement) your dog currently receives," and that "what starts out as a minor problem can change to an emergency over time." fda.gov Retrieved 2026-10-01.
- Center SA, Randolph JF, Warner KL, Simpson KW, Rishniw M. Influence of body condition on plasma prednisolone and prednisone concentrations in clinically healthy cats after single oral dose administration. Research in Veterinary Science. 2013 Aug;95(1):225–30 — "Although interconversion of each drug to the other was confirmed, a single 2mg/kg body weight oral dose of prednisolone produced significantly higher plasma prednisolone concentration (~4-fold higher AUC) compared to prednisone." "Significantly higher plasma drug concentrations in over-conditioned cats (~2-fold) compared to normal-conditioned cats might explain their perceived increased risk for glucocorticoid associated side effects (hepatic lipidosis, diabetes mellitus)." "Findings suggest low comparative bioavailability of oral prednisone compared to prednisolone in cats and consideration of lean body mass or ideal body weight for dosing practices." Conducted in 11 clinically healthy cats as a two-drug crossover trial. PMID 23473553. Abstract via NCBI E-utilities: eutils.ncbi.nlm.nih.gov Retrieved 2026-10-01.
- Cited as evidence of what is currently published, not as clinical sources. SingleCare, Prednisone dosage for dogs: What you should know — chart "Average total daily oral dose": "5–20 | 1.25–5 mg", "20–40 | 5–10 mg", "40–80 | 10–20 mg", "80–160 | 20–40 mg"; "If prednisone is being used as an anti-inflammatory, it is given at doses of 0.5 mg–1 mg/kg per day. If prednisone is being used as an immunosuppressant, it is given at doses of 2–4 mg/kg per day."; "These doses fall within the anti-inflammatory range described above and do not account for health conditions or other factors that may affect a dog's dosage." singlecare.com · A-Z Animals, Prednisone Dosage Chart for Dogs — the identical four bands, no mg/kg figure anywhere on the page, and "This chart is only a reflection of baseline starting doses for mild conditions, such as standard allergies or localized joint inflammation." a-z-animals.com · petdosagechart.com, Prednisone for Dogs — "1 mg per kg (0.45 mg per lb), with once or twice daily (then tapered)" given as "one standard reference" across listed conditions including immune-mediated diseases, alongside "weight alone cannot select the goal, course length, or taper." petdosagechart.com All retrieved 2026-10-01.