Monitor closely
- Decreased appetite
- Vomiting
- Diarrhea or soft stool
- Unusual sleepiness
FDA-approved 4.4mg/kg formula - SID & BID plans
Carprofen Dosage Calculator for Dogs (Rimadyl)
Rimadyl or generic carprofen - enter weight, choose SID or BID, get the right tablet count.
25mg, 75mg, 100mg tablets
Once or twice daily
Long-term monitoring
Prescription aftercare only
Your senior Lab has been on Rimadyl for six months. She gained a little weight and you are wondering if the dose needs adjusting. This calculator is built for exactly that check-in.
Calculator
Rechecking a long-term dose? Check your dog's current weight.
Dosing schedule
Tablet strength
Use case
Age stage
Total daily dose
96.8 mg
Based on 22 kg body weight and the FDA-approved total daily dose of 4.4 mg/kg/day.
Once daily (SID)
96.8 mg
1.3 x 75mg tablets
Twice daily (BID)
48.4 mg x 2
0.6 x 75mg tablets per dose
Which plan is right?
SID is simpler and works well for most dogs. BID may be better if your dog has stomach sensitivity or if your vet specifically recommended it. Always follow your vet's prescribed schedule and never increase the total daily dose without direct vet guidance.
With food
Reduces GI irritation
1-3 hours
Typical onset
Bloodwork
Liver + kidney checks
Do not combine
Other NSAIDs or steroids
Senior dogs are at higher risk for liver and kidney side effects. Bloodwork every 3-6 months is strongly recommended during long-term carprofen use.
Tablet combination finder
Best match for 96.8 mg once daily
Selected: 1.3 x 75mg
Option A: 1 x 100mg
100 mg total, 3.2 mg from target - Closest match
Option B: 0.5 x 25mg + 0.5 x 75mg + 0.5 x 100mg
100 mg total, 3.2 mg from target
Option C: 1 x 25mg + 1 x 75mg
100 mg total, 3.2 mg from target
Carprofen tablets are often scored for splitting, but splitting is still a prescription instruction. Ask your vet if splitting is appropriate for your dog's dose.
Weight change recalculator
Recheck after weight changes
Last calculated weight
22 kg
Dose impact
+0%
New SID dose: 96.8 mg
Long-term monitoring checklist
Next bloodwork: Oct 4, 2026
Educational prescription-aftercare reference only. Do not start, stop, combine, or change carprofen without your veterinarian. The prescription label and clinician instructions remain the source of truth.
What carprofen is used for
Rimadyl is a tablet-first NSAID for inflammatory pain
Carprofen is a prescription nonsteroidal anti-inflammatory drug, or NSAID, approved for dogs. Rimadyl is the best-known brand name, but many generic carprofen tablets are now widely used. The drug is most often prescribed for osteoarthritis, post-operative pain after orthopedic or soft-tissue surgery, and acute inflammatory pain after injury. It helps reduce pain and inflammation, which can make an older dog more willing to rise, walk, climb, rest comfortably, and participate in physical therapy.
Rimadyl became one of the familiar canine pain medications because it was developed specifically for dogs, comes in practical 25mg, 75mg, and 100mg tablet strengths, and is available as chewable tablets that many dogs take easily. The core dose math is simple: the total daily dose is 4.4mg/kg/day. The harder owner question is how that daily amount is scheduled. Some labels give it once daily, while others split the same total into two half-doses every 12 hours.
Carprofen and meloxicam as an alternative NSAID should not be combined. Carprofen is usually tablet-based, while meloxicam often centers on oral-liquid mL measurement. For broader safety context, use the general medication reference.
SID vs BID
Which dosing schedule is better?
SID means once daily. For carprofen, that usually means the full 4.4mg/kg total daily dose is given at one fixed time with food. It is simple, reduces the chance of missed doses, and fits many chronic arthritis plans because the owner only has to remember one daily routine. The tradeoff is that one dose delivers the larger amount at once, so some dogs with sensitive stomachs may not tolerate it as well.
BID means twice daily. The same total daily dose is divided into two 2.2mg/kg doses about 12 hours apart, often breakfast and dinner. BID can be useful when the vet wants smaller per-dose exposure, steadier comfort through the day, or a gentler approach for a dog that had stomach upset on once-daily dosing. The tradeoff is adherence: a missed evening dose or accidental extra dose matters more when the schedule is more complex.
Most vets choose the schedule that best matches the dog, owner routine, pain pattern, and side-effect history. If vomiting or loose stool appears on SID, ask your vet whether BID with the same total daily dose is appropriate. Never increase the total daily amount to chase pain relief. Call the clinic if pain remains uncontrolled.
Dosage charts
Carprofen dosage chart for dogs by weight
These charts use the same formula as the calculator. Tablet counts are mathematical references. Tablets are often scored and can be split, but doses requiring less than a quarter tablet should be discussed with your veterinarian.
SID reference table
4.4mg/kg total daily dose given once daily.
| Weight | Dose | 25mg tablets | 75mg tablets | 100mg tablets |
|---|---|---|---|---|
| 5 kg (11 lbs) | 22 mg | 0.9 | 0.3 | 0.2 |
| 10 kg (22 lbs) | 44 mg | 1.8 | 0.6 | 0.4 |
| 15 kg (33 lbs) | 66 mg | 2.6 | 0.9 | 0.7 |
| 20 kg (44 lbs) | 88 mg | 3.5 | 1.2 | 0.9 |
| 25 kg (55 lbs) | 110 mg | 4.4 | 1.5 | 1.1 |
| 30 kg (66 lbs) | 132 mg | 5.3 | 1.8 | 1.3 |
| 40 kg (88 lbs) | 176 mg | 7.0 | 2.3 | 1.8 |
| 50 kg (110 lbs) | 220 mg | 8.8 | 2.9 | 2.2 |
BID reference table
2.2mg/kg per dose given every 12 hours.
| Weight | Dose | 25mg tablets | 75mg tablets | 100mg tablets |
|---|---|---|---|---|
| 5 kg | 11 mg | 0.4 | 0.15 | 0.1 |
| 10 kg | 22 mg | 0.9 | 0.3 | 0.2 |
| 20 kg | 44 mg | 1.8 | 0.6 | 0.4 |
| 30 kg | 66 mg | 2.6 | 0.9 | 0.7 |
| 40 kg | 88 mg | 3.5 | 1.2 | 0.9 |
Side effects and liver safety
Watch the stomach, liver, and kidneys
Common NSAID side effects include decreased appetite, vomiting, diarrhea, soft stool, and lethargy. More serious signs include black or tarry stool, vomiting blood, yellowing of the gums or eyes, collapse, major weakness, or abnormal thirst and urination. Carprofen is metabolized by the liver. A small percentage of dogs, particularly Labrador Retrievers, have documented idiosyncratic liver reactions that are not simply dose-dependent. This means a reaction can happen even at a correct dose.
Labrador Retrievers and Lab mixes deserve a specific carprofen liver-risk conversation before long-term use. Baseline bloodwork and repeat monitoring are essential.
Call urgently
- Black or tarry stool
- Vomiting blood
- Yellow gums or eyes
- Collapse or severe lethargy
Avoid unless vet approves
- Liver or kidney disease
- Other NSAIDs or steroids
- Dehydration
- Pregnancy or nursing
Rimadyl vs generic
Same active ingredient, different format and price
Rimadyl is the Zoetis brand name. Carprofen is the generic active ingredient. Generic products are widely available and often cost less, while Rimadyl chewables can be easier for some dogs to take because of flavor and consistency. In dosing terms, the milligram strength matters most: 25mg, 75mg, or 100mg. If your dog accepts chewables easily, Rimadyl may be convenient. If budget is the barrier to long-term arthritis management, generic carprofen may be medically equivalent and easier to sustain.
Stopping or switching
Carprofen does not need a taper, but it may need a washout
Carprofen can usually be stopped directly if your vet tells you to stop. The important danger is switching too quickly to another NSAID or a steroid. Many veterinarians use a 5-7 day washout before another NSAID such as meloxicam, and at least 24 hours before some steroid transitions, depending on the case. Other pain supports may include gabapentin for combination pain management, physical therapy, Omega-3s, glucosamine, or weight management.
Frequently asked questions
Carprofen and Rimadyl FAQ
How much carprofen should I give my dog?
The labeled dog dose for carprofen is 4.4 mg/kg/day total. That total daily dose may be given once daily as the full daily amount, often called SID, or split into two 2.2 mg/kg doses about 12 hours apart, often called BID. This calculator converts body weight into both schedules and tablet counts for 25mg, 75mg, and 100mg tablets. The result is a prescription-aftercare math helper, not permission to start the drug. Your veterinarian's written label should decide the exact schedule, tablet strength, duration, monitoring plan, and whether carprofen is appropriate for your dog.
What is the difference between Rimadyl and carprofen?
Rimadyl is a brand name, while carprofen is the active ingredient. Generic carprofen products contain the same active drug, but the tablet form, flavoring, price, and manufacturer can differ. Rimadyl chewables are widely recognized because many dogs accept the beef-flavored tablets easily. Generic products are often less expensive and may be a practical long-term option for arthritis dogs. The dose math is based on carprofen milligrams, not the logo on the package, so a 75mg Rimadyl tablet and a 75mg generic carprofen tablet represent the same active-drug amount.
Can I give my dog carprofen every day long-term?
Many dogs do take carprofen long-term for osteoarthritis, but long-term NSAID use requires monitoring. Baseline bloodwork helps your veterinarian know whether liver and kidney values look safe before starting. Follow-up bloodwork, commonly every 6 months and often every 3-6 months for senior dogs, helps catch problems earlier. Owners should also track appetite, vomiting, diarrhea, stool color, thirst, urination, energy, and jaundice signs. Daily use should be an active management plan with rechecks, not an indefinite refill without current weight, lab work, and veterinary oversight.
How long does carprofen take to work in dogs?
Carprofen often begins improving pain within about 1-3 hours, but the fuller anti-inflammatory benefit for arthritis may take days to a couple of weeks of consistent use. Post-surgery dogs may look more comfortable after early doses, while chronic arthritis dogs are better judged by mobility, willingness to rise, stair use, walk tolerance, and comfort over several days. If your dog is still very painful, refuses food, vomits, develops diarrhea, seems weak, or has black stool, contact your veterinarian rather than simply increasing the dose.
Can I give my dog carprofen and gabapentin together?
Carprofen and gabapentin are commonly prescribed together because they work through different pain pathways. Carprofen is an NSAID for inflammatory pain, while gabapentin is often used for neuropathic pain, post-operative comfort, and multimodal pain control. The combination can be appropriate when your veterinarian prescribes both and gives a schedule. Do not add leftover gabapentin or change either drug on your own. Sedation, kidney status, other pain medications, antacids, and the surgical or arthritis diagnosis can all affect the plan.
What if my dog vomits after taking carprofen?
Carprofen should usually be given with food to reduce stomach irritation. If your dog vomits once shortly after a dose, call your veterinarian for instructions before repeating it, because a second full dose may accidentally double the daily amount. If vomiting continues, diarrhea appears, appetite drops, stool becomes black or tarry, or your dog seems weak, stop and contact the clinic promptly. Your vet may recommend switching from SID to BID using the same total daily dose, changing NSAIDs after an appropriate washout, or using a different pain-control strategy.
Is carprofen safe for senior dogs?
Carprofen can be used in senior dogs, but seniors need a higher monitoring standard. Older dogs are more likely to have kidney disease, liver changes, dehydration risk, other prescriptions, or stomach sensitivity. That does not automatically rule out carprofen, but it makes baseline bloodwork, current body weight, follow-up labs, and careful symptom tracking more important. A senior dog on long-term Rimadyl or generic carprofen should usually have bloodwork every 3-6 months, especially if appetite, stool, thirst, urination, or energy changes.
Can I give my dog carprofen and meloxicam together?
No. Carprofen and meloxicam are both NSAIDs, and combining two NSAIDs increases the risk of stomach ulceration, bleeding, kidney injury, and other serious side effects. Dogs should also not take carprofen with corticosteroids unless a veterinarian has given a specific plan. When switching between NSAIDs, veterinarians typically use a washout period, often around 5-7 days depending on the dog and situation. Do not overlap leftover medications because the pain seems worse; call the veterinarian for a safer transition plan.
Why is my vet recommending bloodwork before carprofen?
Bloodwork gives your veterinarian a baseline for liver and kidney function before a dog starts an NSAID. That matters because carprofen is processed by the liver and NSAIDs can affect kidney blood flow, especially in dehydrated or medically fragile dogs. Baseline values also make later changes easier to interpret. This is especially important for senior dogs, dogs on long-term arthritis treatment, dogs taking other medications, and Labrador Retrievers or Lab mixes because carprofen-related liver reactions have been documented in that breed group.
Related tools
Keep the pain-management context connected
Meloxicam Dosage Calculator
Convert a veterinarian-prescribed meloxicam dose into mg and mL by concentration, with syringe and kidney-safety checks.
Gabapentin Dosage Calculator for Dogs
Convert a veterinarian-prescribed gabapentin range into mg/kg, capsules, and trazodone-combination context.
Dog Weight Calculator
Compare your dog to healthy breed ranges, body condition scoring, and realistic goal-weight timelines.
Sources and disclaimer
Prescription reference, not a dosing order
- Rimadyl prescribing information
- FDA Animal Drugs: carprofen approvals
- VCA Animal Hospitals: carprofen
- ASPCA Animal Poison Control Center
This page helps dog owners understand carprofen prescription math. It should not replace a veterinarian's exam, lab monitoring, written label, or emergency care.