Piroxicam is a potent, long-acting, non-steroidal anti-inflammatory drug (NSAID) of the oxicam class. It is a non-selective cyclooxygenase (COX) inhibitor, exhibiting significant anti-inflammatory, analgesic, and antipyretic properties. Its long half-life allows for once-daily dosing, which can improve patient compliance. In the Indian context, it is widely used for various musculoskeletal disorders but carries a higher risk of gastrointestinal and cardiovascular adverse effects compared to some other NSAIDs, necessitating careful patient selection and monitoring.
Adult: **Osteoarthritis/Rheumatoid Arthritis/Ankylosing Spondylitis:** 20 mg once daily. May be given as a single dose or in divided doses (10 mg twice daily). **Acute Musculoskeletal Disorders/Gout:** 40 mg as a single dose on the first day, followed by 20 mg once daily for the duration of therapy (typically 7-14 days).
Note: Take with food or a full glass of milk/water to minimize gastric irritation. Swallow the capsule/tablet whole; do not crush or chew. For consistent effect, take at the same time each day. The long half-life means missed doses should be taken as soon as remembered, but if it's almost time for the next dose, skip the missed dose. Do not double dose.
Piroxicam exerts its therapeutic effects primarily through the non-selective, reversible inhibition of the enzyme cyclooxygenase (COX), now understood as inhibition of both COX-1 and COX-2 isoforms. This inhibition blocks the conversion of arachidonic acid to prostaglandin G2 and subsequently to prostaglandin H2, the precursor for various prostaglandins (PGs) and thromboxane A2.
Pregnancy: **Category C (First and Second Trimester):** Use only if potential benefit justifies potential fetal risk. Avoid use in late pregnancy (Third Trimester) - **Category D:** Due to risk of premature closure of the ductus arteriosus, oligohydramnios, and inhibition of labor. Should be avoided.
Driving: May cause dizziness, drowsiness, vertigo, or blurred vision. Patients should be cautioned about operating machinery or driving until they know how the medication affects them.
| Warfarin/Acenocoumarol | Increased risk of bleeding due to protein binding displacement and antiplatelet effect of piroxicam. | Major |
| Aspirin (low-dose) or other NSAIDs | Increased risk of GI toxicity (ulcers, bleeding) with no additive therapeutic benefit. | Major |
| Lithium | Decreased renal clearance of lithium, leading to increased lithium levels and toxicity. | Major |
| Methotrexate | Decreased renal clearance of methotrexate, increasing risk of bone marrow suppression and toxicity, especially with high-dose methotrexate. | Major |
| ACE Inhibitors (e.g., Enalapril, Ramipril) / ARBs (e.g., Losartan) | Reduced antihypertensive effect; increased risk of renal impairment, especially in volume-depleted patients. | Moderate |
| Diuretics (e.g., Furosemide, Hydrochlorothiazide) | Reduced diuretic and antihypertensive efficacy; increased risk of renal impairment. | Moderate |
| Corticosteroids (e.g., Prednisolone) | Synergistic increase in risk of GI ulceration and bleeding. | Moderate |
| Selective Serotonin Reuptake Inhibitors (SSRIs e.g., Sertraline) | Increased risk of upper GI bleeding. | Moderate |
| Antiplatelets (e.g., Clopidogrel) | Increased risk of GI bleeding. | Moderate |
| Cyclosporine | Increased risk of nephrotoxicity. | Moderate |
| Sulfonylureas (e.g., Glimepiride) | Potential for hypoglycemia due to protein binding displacement. | Moderate |
Same composition (Piroxicam (NA)), different brands: