Overview
Tenoxicam is a nonsteroidal anti-inflammatory drug (NSAID) of the oxicam class, used for its analgesic, anti-inflammatory, and antipyretic properties. It is indicated for the management of pain and inflammation associated with musculoskeletal disorders such as osteoarthritis, rheumatoid arthritis, and acute gout. Tenoxicam works by inhibiting cyclooxygenase (COX) enzymes, thereby reducing prostaglandin synthesis. It has a long half-life, allowing for once-daily dosing. Due to its NSAID class, it carries risks of gastrointestinal, cardiovascular, and renal adverse effects, and should be used at the lowest effective dose for the shortest duration.
Mechanism of Action
Tenoxicam is a nonselective inhibitor of cyclooxygenase (COX-1 and COX-2) enzymes. This inhibition reduces the conversion of arachidonic acid to prostaglandins, thromboxanes, and prostacyclins, which are mediators of inflammation, pain, and fever. By decreasing prostaglandin synthesis, it alleviates symptoms of inflammation and pain but also contributes to gastrointestinal and renal side effects due to reduced cytoprotective prostaglandins.
Indications
- Osteoarthritis
- Rheumatoid arthritis
- Ankylosing spondylitis
- Acute musculoskeletal disorders
- Acute gout
Dosage
The usual adult dose is 20 mg once daily, taken with food to minimize gastrointestinal upset. For acute conditions, a loading dose of 40 mg may be used on the first day, followed by 20 mg daily. The maximum daily dose is 40 mg. Dosage should be individualized based on patient response and tolerability, and used at the lowest effective dose for the shortest possible duration.
Contraindications
- Hypersensitivity to tenoxicam, other NSAIDs, or any component of the formulation
- History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs
- Active peptic ulcer disease or gastrointestinal bleeding
- Severe heart failure
- Severe renal impairment
- Third trimester of pregnancy
- Concomitant use with other NSAIDs including COX-2 inhibitors
Side Effects
- Common: Dyspepsia, nausea, abdominal pain, diarrhea, headache, dizziness
- Serious: Gastrointestinal bleeding, peptic ulcer, renal impairment, hepatotoxicity, hypertension, heart failure, anaphylactic reactions, severe skin reactions
- Other: Edema, fatigue, rash, tinnitus, increased liver enzymes
Interactions
- Anticoagulants (e.g., warfarin): Increased risk of bleeding
- Antiplatelet agents (e.g., aspirin): Increased risk of gastrointestinal bleeding
- ACE inhibitors/ARBs: Reduced antihypertensive effect and risk of renal impairment
- Diuretics: Reduced diuretic efficacy and risk of renal impairment
- Lithium: Increased lithium levels and toxicity
- Methotrexate: Increased methotrexate toxicity
- Corticosteroids: Increased risk of gastrointestinal ulceration
- Selective serotonin reuptake inhibitors (SSRIs): Increased risk of bleeding