COX-2 Selective NSAIDPrescription Only Black Box Warning

Celebrex®

Celecoxib

Pfizer (brand) / Generic since 2014·FDA December 1998·
50 mg100 mg200 mg400 mg

Version 2025-04 · Last reviewed April 1, 2025 · Methodology

List Price

$310

With Insurance

$15–40 (generic)

FDA Black Box Warning

CARDIOVASCULAR THROMBOTIC EVENTS & SERIOUS GI RISK

COX-2 selective and non-selective NSAIDs carry the same class-wide black box for MI and stroke risk — risk increases with dose and duration. Same black box for GI ulcers, bleeding, and perforation. Not for use in perioperative pain from CABG surgery.

Strict Contraindications

History of MI or strokePerioperative CABG surgery painKnown NSAID or sulfonamide hypersensitivitySevere heart failure

How It Works

Celecoxib selectively inhibits the COX-2 enzyme — an inducible enzyme upregulated at sites of inflammation, injury, and fever. It largely spares COX-1, the constitutive enzyme that protects the stomach lining and enables platelet clotting. The COX-2 "selectivity" was the entire marketing premise after Vioxx — the idea being that you could block inflammation without causing stomach ulcers. The cardiovascular catch emerged immediately: COX-2 produces prostacyclin (PGI2), a potent vasodilator and antiplatelet molecule in blood vessel walls. Block COX-2, and PGI2 drops. COX-1's thromboxane A2 (TXA2 — pro-clotting, pro-vasoconstriction) is left unopposed. The result is a prothrombotic imbalance that tilts the vascular environment toward clot formation — the same mechanism that caused Vioxx to kill an estimated 38,000 Americans. Celecoxib has more balanced COX-1/2 selectivity than rofecoxib (Vioxx), which is why it survived the class-wide reckoning of 2004 — but the mechanism and the black box warning are the same.

Selective competitive inhibitionCOX-2 (cyclooxygenase-2)
Blocks prostaglandin E2 (PGE2) and prostacyclin (PGI2) synthesis at inflammatory sites — reduces pain, fever, and local inflammation
Largely spared (unlike non-selective NSAIDs)COX-1 (cyclooxygenase-1)
Protects gastric mucosa and maintains platelet TXA2 production — source of the GI advantage (and the cardiovascular liability at the PGI2/TXA2 balance)
Reduced by COX-2 blockadeProstacyclin (PGI2) in endothelium
Vascular PGI2 drops → loss of vasodilation and platelet inhibition in blood vessels → relative excess of platelet-activating TXA2 → prothrombotic environment
Substrate and partial inhibitorCYP2C9 (drug metabolism enzyme)
Celecoxib is metabolized by CYP2C9 and partially inhibits it — raises plasma levels of warfarin, causing significant drug interactions

Why the side effects happen

The cardiovascular risk (MI, stroke) flows directly from the mechanism: suppressing vascular PGI2 while leaving platelet TXA2 active tilts coagulation toward clot formation. Blood pressure rises because prostacyclin is also a renal vasodilator — lose it and sodium retention follows. The GI advantage is real but dose-dependent and time-limited — as the CLASS trial 12-month data showed, the advantage disappears with ongoing use, and patients on aspirin have zero GI advantage at all since aspirin itself causes GI mucosal damage. Kidney injury follows the same mechanism as all NSAIDs: prostaglandins maintain renal perfusion in states of reduced blood flow — block them and kidney function falls, especially in elderly, dehydrated, or volume-depleted patients.

When Will I Feel It?

Celecoxib reaches peak plasma levels in 2–4 hours with meaningful anti-inflammatory effect by day 1–2, but full arthritis benefit may take 2–4 weeks. Cardiovascular risk begins immediately and persists for the duration of use.

1
Hour 2–42–4 hours

Peak blood levels. Acute pain reduction begins. Platelet/vascular effects (prothrombotic imbalance) also begin at first dose.

2
Days 1–7First week

Acute pain and inflammation noticeably improved. Blood pressure monitoring recommended — sodium retention begins within days.

3
Weeks 2–42–4 weeks

Full anti-inflammatory benefit for OA and RA — synovial prostaglandin levels normalized. Continue blood pressure and kidney function monitoring.

4
Month 6+>6 months

The 12-month CLASS trial data showed GI advantage disappears by month 12. Cardiovascular risk accumulates with duration of exposure. Reassess every 3–6 months whether NSAID continuation is warranted.

Medical Disclaimer

The information on this page is compiled from publicly available clinical trial data, FDA prescribing information, and peer-reviewed literature. It is provided for educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Individual responses to medications vary. Always consult a qualified healthcare provider before starting, stopping, or changing any medication.

Common Side Effects

While taking this medication, you may experience the following common side effects. We've included tips on how to manage them.

Hypertension / elevated blood pressure

13%

Monitor BP within 2–4 weeks of starting; NSAIDs cause sodium retention. This effect persists even with COX-2 selectivity.

Headache

15%

Usually mild and resolves within the first 2 weeks; ensure adequate hydration

Diarrhea

11%

Generally mild; reduces with food co-administration

Abdominal pain / dyspepsia

8%

Take with food; celecoxib causes significantly less GI damage than non-selective NSAIDs — but it is not risk-free, especially at higher doses or with alcohol

Peripheral edema / fluid retention

4–5%

Report ankle swelling; especially relevant in patients with heart failure or on diuretics

Dizziness

5%

Avoid driving until effect is known; increases fall risk in elderly

Rhinitis / upper respiratory symptoms

5%

Usually mild and non-allergic; monitor for signs of hypersensitivity (hives, bronchospasm) especially in aspirin-sensitive asthma

Serious Adverse Effects

  • Myocardial infarction (MI) and stroke — black box; same class-wide risk as all NSAIDs including Vioxx; risk increases with dose and duration
  • GI ulcers and bleeding — less than non-selective NSAIDs at 6 months, but CLASS trial showed advantage disappears at 12 months
  • Acute kidney injury — NSAIDs reduce prostaglandin-mediated renal perfusion; dangerous in dehydration, elderly, or with ACE inhibitors/diuretics
  • Hepatotoxicity — rare but reported; monitor liver enzymes in long-term use
  • Severe skin reactions (SJS/TEN) — rare; stop immediately at first sign of rash
  • Exacerbation of heart failure — sodium retention worsens fluid overload
  • Aspirin-sensitive asthma — COX-2 inhibitors can still trigger bronchoconstriction in aspirin-sensitive patients

Drug Interactions

Major Interactions (Avoid)

Warfarin (Coumadin)Celecoxib inhibits CYP2C9 — the enzyme that metabolizes warfarin. Raises warfarin levels significantly, increasing bleeding risk. Monitor INR within 1 week of starting and after any dose change.
Aspirin (combined GI risk)Combining celecoxib with aspirin eliminates its GI safety advantage and increases ulcer/bleeding risk. Ironically, the PRECISION trial's "good results" depended on 90% of patients being on aspirin — negating the very mechanism that makes COX-2 inhibitors more dangerous for the heart.

Moderate Interactions (Caution)

ACE inhibitors / ARBs (lisinopril, losartan)NSAIDs blunt antihypertensive efficacy and increase acute kidney injury risk, especially in elderly or dehydrated patients.
LithiumNSAIDs reduce renal lithium clearance — celecoxib can raise lithium levels by 17–25% into toxic range. Monitor lithium levels.
MethotrexateNSAIDs reduce renal methotrexate clearance — serious toxicity risk in oncology and rheumatology patients. Use with great caution.
SSRIs (sertraline, fluoxetine)Both SSRIs and NSAIDs impair platelet function independently — combined use increases GI bleeding risk substantially.
Fluconazole (antifungal)Strong CYP2C9 inhibitor — doubles celecoxib blood levels. Reduce celecoxib dose by 50% if co-administering.

Food Interactions

AlcoholBoth alcohol and NSAIDs damage the gastric mucosa — even though celecoxib causes less GI damage than non-selective NSAIDs, alcohol removes that advantage. Do not drink while taking NSAIDs regularly.
High-fat mealHigh-fat meals increase celecoxib absorption by 10–20% — clinically minor but relevant at high doses.

When to Contact Your Doctor

This medication requires ongoing medical supervision. The following situations warrant a prompt conversation with your prescribing physician — do not wait for your next scheduled appointment.

Contact soon if you notice

  • Myocardial infarction (MI) and stroke — black box; same class-wide risk as all NSAIDs including Vioxx; risk increases with dose and duration
  • GI ulcers and bleeding — less than non-selective NSAIDs at 6 months, but CLASS trial showed advantage disappears at 12 months
  • Acute kidney injury — NSAIDs reduce prostaglandin-mediated renal perfusion; dangerous in dehydration, elderly, or with ACE inhibitors/diuretics
  • Hepatotoxicity — rare but reported; monitor liver enzymes in long-term use
  • Black, tarry, or bloody stools — GI bleeding; stop immediately and seek emergency care

Also discuss if you want to

  • Review whether this medication is still appropriate for you
  • Consider dosage adjustments based on response
  • Explore lifestyle or non-drug alternatives
  • Understand stopping or tapering options
  • Plan monitoring labs and follow-up

In the US, call 911 or go to the nearest emergency room for severe symptoms. Poison Control: 1-800-222-1222.

Special Populations

Safety classifications for specific groups — discuss with your provider before use.

AVOID — Especially 20+ WeeksPregnancy

From 20 weeks onward: causes fetal kidney dysfunction and oligohydramnios (low amniotic fluid) — FDA warning 2020. First trimester: potential miscarriage risk. Celecoxib is a sulfonamide — additional allergy concern. Use acetaminophen for pain during pregnancy.

Caution — Minimal DataBreastfeeding

Limited data on transfer to breast milk. Occasional use likely low risk; avoid long-term or high-dose use. Ibuprofen (better-studied) is generally preferred for nursing mothers who need an NSAID.

Cardiovascular Risk Amplified Post-MenopauseMenopause / Hormonal

Estrogen provided cardiovascular protection. After menopause that protection is lost — adding a COX-2 inhibitor on top of this increased baseline cardiovascular risk compounds the concern. The same black box warning applies regardless of age, but post-menopausal women are in the highest-risk demographic for NSAID-related cardiovascular events.

Approved ≥2 Years (JIA Only)Children & Teens

FDA-approved for juvenile idiopathic arthritis (JIA) in children ≥2 years. Not approved for general pain or fever in children — ibuprofen is the evidence-based OTC option. Celecoxib is not appropriate as a substitute for ibuprofen in children.

HIGH RISK — Beers CriteriaOlder Adults

All NSAIDs, including COX-2 selective agents, are on the AGS Beers Criteria as high-risk in older adults. Celebrex does not escape this classification. Increased risk of GI bleeding, MI, heart failure exacerbation, and acute kidney injury. Use lowest dose for shortest time, with a PPI if unavoidable.

Avoid in Severe ImpairmentKidney Disease

Celecoxib is not recommended in severe renal impairment (eGFR <30). All NSAIDs reduce prostaglandin-dependent renal perfusion — causing acute kidney injury in patients with reduced renal reserve, dehydration, or volume depletion.

Reduce Dose in Moderate ImpairmentLiver Disease

Reduce dose by 50% in moderate hepatic impairment (Child-Pugh Class B). Avoid in severe hepatic impairment. Celecoxib is hepatically metabolized via CYP2C9 — impaired metabolism increases exposure and toxicity risk.

FDA Adverse Event Reports

Patient-filed reports from the FDA FAERS database · refreshed daily

Anecdotal data. Reports are not confirmed causation. Always consult your provider.

Community Reports

User-reported experiences — anonymous & anecdotal

Medical Disclaimer

The information on this page is compiled from publicly available clinical trial data, FDA prescribing information, and peer-reviewed literature. It is provided for educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Individual responses to medications vary. Always consult a qualified healthcare provider before starting, stopping, or changing any medication.

Metabolic & Lifestyle Alternatives

Pain & Inflammation Without Cardiovascular or GI Compromise

The COX-2 "selectivity" was always a GI marketing story — Vioxx and the CLASS trial proved the cardiovascular and long-term GI risks remain. Curcumin matched ibuprofen for knee OA pain in a head-to-head RCT with no cardiovascular, renal, or thrombotic risk.

Important context: Evidence quality varies across these approaches. Some are well-studied with randomized controlled trial data; others are based on observational or smaller studies. These interventions are not guaranteed to replace medication for all patients. Discuss with your doctor whether any of these are appropriate for your clinical situation.

Global Prescribing & Pricing

COX-2 inhibitors are prescribed more cautiously in Europe post-Vioxx; the UK NICE explicitly restricts celecoxib to patients at high GI risk who cannot tolerate non-selective NSAIDs

🇺🇸

United States

$20–60 (generic)/mo

Rate

Heavily prescribed; still marketed by Pfizer with the GI advantage narrative despite the black box

Policy

No prerequisite GI risk assessment required before prescribing; DTC advertising allowed

Cover

Often covered; prior auth sometimes required for brand

🇬🇧

United Kingdom

~$12–25/mo

Rate

NICE CG177: only recommended in patients with documented high GI risk who have failed standard NSAIDs; lowest effective dose for shortest time

Policy

GP must document GI risk reason for COX-2 selection; NICE explicitly states COX-2 selectivity does not eliminate cardiovascular risk

Cover

Covered by NHS with documented indication

🇩🇪

Germany

~$15–30/mo

Rate

G-BA (benefit assessment agency) rates celecoxib as "no added benefit" over non-selective NSAIDs in most patients given equivalent cardiovascular risk

Policy

Statutory insurers may restrict reimbursement without documented GI risk indication; cardiovascular risk assessment mandatory

Cover

Covered with documented GI indication

🇫🇷

France

~$10–25/mo

Rate

HAS (French drug agency) restricted COX-2 inhibitor reimbursement post-Vioxx; similar restriction to UK — high GI risk plus contraindication to non-selective NSAID

Policy

Pharmacist required to document GI risk history; lower prescribing rate than US

Cover

Covered only with specific documented GI risk

🇦🇺

Australia

~$15–30/mo

Rate

TGA-approved; PBS subsidy restricted to patients with high GI risk — requires documented history of GI ulcer or bleeding

Policy

PBS authority required; cardiovascular risk assessment strongly encouraged before initiation; no DTC advertising allowed

Cover

PBS covered with authority script

After Vioxx killed an estimated 38,000 Americans, regulatory agencies worldwide tightened COX-2 inhibitor prescribing. The UK, Germany, France, and Australia now restrict reimbursement to patients with documented high GI risk — acknowledging that COX-2 selectivity does not reduce cardiovascular risk and that the GI advantage disappears in patients on aspirin. The US remains the outlier, permitting DTC advertising and unrestricted prescribing.

Clinical Trials & Funding

Understanding who funds research helps contextualize results. Industry-funded trials are not automatically invalid — they undergo the same FDA review — but declared conflicts and sponsor effects are worth knowing. All linked trials can be verified on ClinicalTrials.gov.

Funding Sources

The CLASS trial (Celecoxib Long-term Arthritis Safety Study) was funded by Pfizer and published in JAMA 2000. The JAMA publication reported only 6-month data showing GI superiority — while Pfizer held 12-month data showing the advantage disappeared. The FDA revealed the full dataset only after external pressure. The PRECISION trial was also Pfizer-funded and enrolled ~90% of participants already on low-dose aspirin — a population in which aspirin itself blocks the platelet COX-1 pathway, chemically masking the exact cardiovascular risk that distinguishes COX-2 inhibitors from non-selective NSAIDs.

Declared Conflicts of Interest

Pfizer's Celebrex marketing team rebuilt the brand after Merck's Vioxx withdrawal (2004) using CLASS and PRECISION data. Key trial investigators had Pfizer financial ties. Pfizer controls patient-level data for all pivotal trials. The selective publication of CLASS 6-month vs. 12-month data is one of the most cited examples of publication bias in academic medicine. Celecoxib's cardiovascular black box warning remained throughout — but was consistently minimized in marketing relative to the GI advantage.

Key Efficacy Results

CLASS: GI advantage shown at 6 months — disappeared at 12 months (12-month data suppressed). PRECISION: Non-inferior to ibuprofen and naproxen for CV safety — but 90% of patients were on aspirin, which masks COX-2 selective cardiovascular risk.

Evidence & Transparency

Cochrane RoB-2 (Risk of Bias)

Badges reflect an editorial assessment using Cochrane's RoB-2 tool domains: randomization, intervention deviation, missing data, outcome measurement, and selective reporting. These are not certified Cochrane reviews. Learn more ↗

CMS Open Payments

Manufacturer payment disclosures are reported via the CMS Sunshine Act. Disclosure is legally required and does not imply bias or misconduct. Language uses "may," "suggests," or "appears" — never definitive clinical claims. CMS Open Payments ↗

Live Clinical Trials

Live from ClinicalTrials.gov · refreshed every 4 hours

Currently enrolling, active, and recently completed studies involving Celecoxib. Data is pulled directly from the U.S. National Library of Medicine.

Recent Research

Live from PubMed · peer-reviewed literature · refreshed every 4 hours

Most recently indexed clinical trials and systematic reviews mentioning Celecoxib in PubMed.

Source Documentation

Structured citations for referenced clinical trials

Each referenced trial is listed with its registry ID, funding source, and bias assessment. Use the copy button to generate a formatted citation.

TrialRegistry IDCite
CLASS Trial — JAMA 2000 (6-month only)PMID:10983798
Juni et al. — Full 12-Month CLASS Data (Lancet 2002)PMID:12427958
PRECISION Trial (NEJM 2016)PMID:27356222

Bias ratings use Cochrane RoB-2 methodology. Editorial assessment — not a certified Cochrane review.

Our Methodology

Medical Disclaimer

The information on this page is compiled from publicly available clinical trial data, FDA prescribing information, and peer-reviewed literature. It is provided for educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Individual responses to medications vary. Always consult a qualified healthcare provider before starting, stopping, or changing any medication.

Stopping This Medication Safely

No Taper DocumentedDocumented timeframe: Research indicates no pharmacological withdrawal risk

Celecoxib does not cause physical dependence and can be stopped at any time. Underlying inflammatory pain will return — address the root cause rather than taking an indefinite NSAID with cardiovascular risk.

What Published Research Shows About Stopping This Medication

This summarizes what published research documents — it is not personal medical advice. Any changes to your medication require discussion with your prescribing physician.

  • ·Research shows no pharmacological taper is needed for celecoxib
  • ·Research supports addressing the root cause of pain (weight management, physical therapy, omega-3, curcumin) rather than restarting
  • ·For patients stopping due to GI or cardiovascular concern, research supports acetaminophen for pain and non-NSAID alternatives
  • ·Research documents that abruptly switching from celecoxib to high-dose aspirin can cause significant GI bleeding due to combined platelet effects

Warning Symptoms — Contact Your Doctor If You Experience:

  • Black, tarry, or bloody stools — GI bleeding; stop immediately and seek emergency care
  • Chest pain, shortness of breath, sudden weakness — cardiovascular event; call 911
  • Severe swelling, rapid weight gain, decreased urination — kidney failure
  • Skin rash, blistering, or peeling — possible SJS/TEN; stop immediately

Never change or stop a medication without consulting your prescribing physician.

Questions for Your Doctor

Questions to Ask

  • 1.I take low-dose aspirin for heart protection — is Celebrex still safer for my stomach in that case, or does the aspirin eliminate that advantage?
  • 2.I have a history of MI or stroke — should I be taking any NSAID, or are there safer alternatives for my pain?
  • 3.I'm on warfarin — how do I monitor for the interaction between celecoxib and my blood thinner?
  • 4.Is my kidney function adequate for NSAID use, and how do we monitor it?
  • 5.Has a trial of curcumin, omega-3, or physical therapy been tried first for my condition?

Lab Tests to Request

  • Blood pressure (baseline and 2–4 weeks after starting)
  • Kidney function (eGFR + creatinine)
  • INR if on warfarin — within 1 week of starting
  • Hemoglobin / CBC if used chronically (GI blood loss)
  • Liver enzymes (ALT/AST) — baseline and periodically in long-term use

Medical Disclaimer

The information on this page is compiled from publicly available clinical trial data, FDA prescribing information, and peer-reviewed literature. It is provided for educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Individual responses to medications vary. Always consult a qualified healthcare provider before starting, stopping, or changing any medication.

Frequently Asked Questions About Celebrex®

What is Celebrex® used for?
Celebrex® (Celecoxib) is a COX-2 Selective NSAID manufactured by Pfizer (brand) / Generic since 2014. FDA-approved indications include: Osteoarthritis; Rheumatoid arthritis; Ankylosing spondylitis; Acute pain; Primary dysmenorrhea; Juvenile idiopathic arthritis (JIA, ≥2 years).
What are the common side effects of Celebrex®?
Common side effects of Celebrex® include: Hypertension / elevated blood pressure (13%); Headache (15%); Diarrhea (11%); Abdominal pain / dyspepsia (8%); Peripheral edema / fluid retention (4–5%).
How much does Celebrex® cost?
Celebrex® list price is approximately $310. With insurance it typically costs $15–40 (generic); without insurance approximately $20–60 (generic) · $280–320 (brand).
Who funded the clinical trials for Celebrex®?
The CLASS trial (Celecoxib Long-term Arthritis Safety Study) was funded by Pfizer and published in JAMA 2000. The JAMA publication reported only 6-month data showing GI superiority — while Pfizer held 12-month data showing the advantage disappeared. The FDA revealed the full dataset only after external pressure. The PRECISION trial was also Pfizer-funded and enrolled ~90% of participants already on low-dose aspirin — a population in which aspirin itself blocks the platelet COX-1 pathway, chemically masking the exact cardiovascular risk that distinguishes COX-2 inhibitors from non-selective NSAIDs.
How strong is the clinical evidence for Celebrex®?
Key studies: CLASS trial (2000) — selective publication scandal; PRECISION trial (2016) — 90% of patients on aspirin. CLASS: GI advantage shown at 6 months — disappeared at 12 months (12-month data suppressed). PRECISION: Non-inferior to ibuprofen and naproxen for CV safety — but 90% of patients were on aspirin, which masks COX-2 selective cardiovascular risk. Potential conflicts of interest: Pfizer's Celebrex marketing team rebuilt the brand after Merck's Vioxx withdrawal (2004) using CLASS and PRECISION data. Key trial investigators had Pfizer financial ties. Pfizer controls patient-leve.
Are there non-drug alternatives to Celebrex®?
The COX-2 "selectivity" was always a GI marketing story — Vioxx and the CLASS trial proved the cardiovascular and long-term GI risks remain. Curcumin matched ibuprofen for knee OA pain in a head-to-head RCT with no cardiovascular, renal, or thrombotic risk. See the Alternatives tab for full details.

Get notified when we update Celebrex®

We'll email you when new evidence, safety updates, or alternatives are added.

No spam. Unsubscribe anytime.