Meloxicam
Meloxicam
Generic Name
Meloxicam
Mechanism
- Meloxicam is a non‑steroidal anti‑inflammatory drug (NSAID) that selectively inhibits cyclooxygenase‑2 (COX‑2) at therapeutic doses, sparing COX‑1 to a greater extent than non‑selective NSAIDs.
- By blocking COX‑2, it prevents the conversion of arachidonic acid to prostaglandin E₂ (PGE₂), a key mediator of pain, fever, and inflammation.
- The relative COX‑2 selectivity reduces gastric mucosal prostaglandin production, thereby lowering the risk of gastric ulceration compared with older NSAIDs.
- Long‑acting intracellular inhibition of COX‑2 results in an effective anti‑inflammatory response with once‑daily dosing.
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Pharmacokinetics
- Absorption: Rapid oral absorption; peak plasma concentration 1–2 h post‑dose.
- Bioavailability: ~70–80 %, unaffected by food.
- Distribution: Highly protein‑bound (≈97 % to albumin and α‑1‑acid glycoprotein).
- Metabolism: Hepatic, primarily oxidative pathways via CYP2C9 and CYP3A4; metabolites are inactive.
- Excretion: Renal (≈60 % unchanged) and biliary (≈20 %).
- Half‑life: 20–27 h, allowing once‑daily administration.
- Steady state: Achieved in ~72 h; accumulation possible in renal or hepatic impairment.
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Indications
- Rheumatoid arthritis (RA) – maintenance and flare management.
- Osteoarthritis (OA) – symptomatic pain relief.
- Ankylosing spondylitis – active disease control.
- Other inflammatory arthropathies – psoriatic arthritis, juvenile idiopathic arthritis.
- Acute musculoskeletal pain – short‑term adjunctive analgesia.
- Primary dysmenorrhea (at lower doses) – short‑term relief.
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Dosing
| Indication | Typical Regimen | Notes |
| Rheumatoid arthritis | 15 mg PO once daily (or 30 mg once daily with 1 week break) | May begin at 7.5 mg for rapid onset, then titrate. |
| Osteoarthritis/ankylosing spondylitis | 15 mg PO once daily | Dose may be increased to 30 mg if tolerated. |
| Acute pain or post‑operative | 2.5 mg PO 4–6 h apart up to 10 mg/day | Short‑term use; avoid chronic dosing. |
| Primary dysmenorrhea | 2.5 mg PO at onset of cramping (break‑through) | Not for long‑term use. |
• Administration: Take with food or milk to reduce GI irritation; avoid with high‑fat meals that delay absorption.
• Maintenance: Re‑evaluate tolerability and efficacy periodically; consider drug holidays (e.g., 1‑week break every 4–6 weeks) in chronic therapy to mitigate cumulative GI risk.
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Monitoring
| Parameter | Frequency | Rationale |
| Serum creatinine, BUN, eGFR | Baseline; every 3–6 months in chronic users | Detect renal impairment early. |
| Blood pressure | Baseline; monthly in chronic therapy | Monitor for hypertension or fluid retention. |
| Liver function tests (AST, ALT, bilirubin) | Baseline; annually | Identify hepatotoxicity. |
| Complete blood count | Baseline; yearly | Identify leukopenia, anemia, thrombocytopenia. |
| Urinalysis | Baseline; as indicated | Detect hematuria or proteinuria. |
| Abdominal pain or melena | As symptomatic | Early GI bleed recognition. |
| Pregnancy test | Baseline; before each trimester | Avoid teratogenic risk. |
| Drug interactions | At initiation and any new medication | Prevent additive NSAID or anticoagulant effects. |
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Clinical Pearls
1. COX‑2 Selectivity – Meloxicam’s greater COX‑2 to COX‑1 ratio (~20:1 at therapeutic doses) lowers GI ulcer risk compared with older NSAIDs, yet it still retains cardiovascular vigilance.
2. Long Half‑Life – The 20–27 h half‑life allows true once‑daily dosing, which improves adherence and reduces peak‑to‑trough fluctuations in pain control.
3. High‑Risk Populations – In patients with coronary stents, consider continuing aspirin and avoid adding another NSAID; instead, switch to acetaminophen or ibuprofen (if needed) after a washout period.
4. Renal Compromise – For patients on ACE inhibitors or ARBs, monitor serum creatinine weekly during the first month; if eGFR falls <30 mL/min, discontinue meloxicam.
5. Gastro‑intestinal Protection – Co‑prescribe proton‑pump inhibitors (PPIs) or misoprostol if symptoms develop or in long‑term therapy, especially when other GI‑risk factors are present.
6. Drug‑Drug Interaction Alert – Meloxicam can potentiate warfarin’s anticoagulation; monitor INR twice weekly when starting or changing doses.
7. Pregnancy‑Specific Care – While melting in the first trimester can be considered with informed consent, avoid any NSAID beyond 20 weeks due to risk of premature ductus arteriosus closure.
8. Dose Increment Strategy – Begin at 7.5–10 mg for RA flares; if inadequate, titrate to 15 mg then to 30 mg (max 30 mg once daily) while observing tolerance.
9. Infection‑Triggered Dosing – In acute inflammatory arthritis flares, a short 2.5 mg BID dosing may yield rapid relief; however, limit to under 5 days to avoid adverse events.
10. Patient Education – Emphasize to patients that gastrointestinal side‑effects may appear only after days of therapy; prompt reporting of upper abdominal pain, vomiting blood, or black stools is essential.
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• Key Takeaway: Meloxicam offers effective, long‑acting anti‑inflammatory therapy with a relatively favorable GI profile due to COX‑2 selectivity, but requires vigilant monitoring of renal, hepatic, cardiovascular, and GI parameters, particularly in high‑risk populations.