Etoricoxib Tablet: A COX-2 Selective Non-Steroidal Anti-Inflammatory Drug (NSAID)

Etoricoxib Tablet is a potent and orally active cyclooxygenase-2 (COX-2) specific inhibitor. It belongs to the class of Non-steroidal Anti-inflammatory Drugs (NSAIDs) and is used for the symptomatic relief of pain and inflammation in various musculoskeletal and inflammatory conditions.

How Etoricoxib Works (Pharmacology)

Etoricoxib selectively inhibits COX-2, an enzyme primarily responsible for synthesizing prostanoid mediators of pain, inflammation, and fever. Unlike nonselective NSAIDs, Etoricoxib (at clinical doses) significantly inhibits COX-2 without inhibiting COX-1. COX-1 is responsible for protective physiological functions like gastric cytoprotection and platelet aggregation. This selective action of Etoricoxib aims to reduce pain and inflammation while minimizing the potential for gastrointestinal toxicity and effects on platelet aggregation commonly seen with nonselective NSAIDs. Etoricoxib has been shown to produce dose-dependent COX-2 inhibition without inhibiting gastric prostaglandin synthesis at doses up to 150 mg daily.

Key Indications & Benefits

Etoricoxib is indicated for the symptomatic relief of:

• Osteoarthritis (OA)
• Rheumatoid arthritis (RA)
• Ankylosing spondylitis
• Pain and signs of inflammation associated with acute gouty arthritis
• Short-term treatment of moderate pain associated with dental surgery

Dosage & Administration

Etoricoxib tablets can be taken without regard to meals. As the cardiovascular risks of Etoricoxib may increase with dose and duration of exposure, the shortest possible duration and the lowest effective daily dose should be used. The patient's need for symptomatic relief and response to therapy should be re-evaluated periodically. Always consult a registered physician for medication use.

Adult and Adolescent over 16 years:

• Osteoarthritis: Recommended dose is 30 mg once daily. In some patients with insufficient relief, the dose may be increased to 60 mg once daily.
• Rheumatoid arthritis: Recommended dose is 90 mg once daily.
• Ankylosing spondylitis: Recommended dose is 90 mg once daily.
• Acute gouty arthritis: Recommended dose is 120 mg once daily. In clinical trials, it was given for 8 days.
• Postoperative dental surgery pain: Recommended dose is 90 mg once daily, limited to a maximum of 3 days. Some patients may require additional postoperative analgesia.

Important Considerations & Warnings

It is crucial to discuss your full medical history with your doctor before taking Etoricoxib.

Contraindications:

• Hypersensitivity to Etoricoxib or any excipients.
• Active peptic ulceration or active gastrointestinal (GI) bleeding.
• Patients who have experienced bronchospasm, acute rhinitis, nasal polyps, angioneurotic oedema, urticaria, or allergic-type reactions after taking acetylsalicylic acid (aspirin) or other NSAIDs (including other COX-2 inhibitors).
• Pregnancy and lactation.
• Severe hepatic dysfunction (serum albumin <25 g/l or Child-Pugh score ≥ 10).
• Estimated renal creatinine clearance <30 ml/min.
• Children and adolescents under 16 years of age.
• Inflammatory bowel disease.
• Congestive heart failure (NYHA II-IV).
• Patients with hypertension whose blood pressure is persistently elevated above 140/90 mmHg and has not been adequately controlled.
• Established ischaemic heart disease, peripheral arterial disease, and/or cerebrovascular disease.

Side Effects:

• Common: Palpitation, fatigue, influenza-like symptoms, ecchymosis.
• Less common: Dry mouth, taste disturbance, mouth ulcer, appetite and weight change, atrial fibrillation, transient ischaemic attack, chest pain, flushing, cough, dyspnoea (shortness of breath), epistaxis (nosebleed), anxiety, impaired mental acuity, paraesthesia (numbness/tingling), electrolyte disturbance, myalgia (muscle pain), and arthralgia (joint pain).
• Very rarely: Confusion and hallucinations.

Pregnancy & Lactation:

• Pregnancy: The use of Etoricoxib is not recommended in women attempting to conceive. There is insufficient data on human pregnancy, and inhibition of prostaglandin synthesis can adversely affect pregnancy.
• Lactation: It is not known whether Etoricoxib is excreted in human milk. However, it is excreted in the milk of lactating rats. Therefore, women who use Etoricoxib must not breastfeed.

Precautions & Warnings:

• Gastrointestinal Risk: Caution advised in patients at high risk of GI complications (elderly, those on other NSAIDs or aspirin, or with a history of GI disease like ulcers/bleeding).
• Cardiovascular Risk: Patients with significant risk factors for cardiovascular events (e.g., hypertension, hyperlipidaemia, diabetes mellitus, smoking) should be treated only after careful consideration. Cardiovascular risks may increase with dose and duration.
• Renal Function: May cause a reduction in prostaglandin formation and renal blood flow, potentially impairing renal function. Monitoring of renal function should be considered in at-risk patients. Caution in patients with a history of cardiac failure, left ventricular dysfunction, hypertension, and pre-existing edema.
• Hepatic Function: Monitor patients with symptoms/signs suggesting liver dysfunction or abnormal liver function tests. Discontinue if signs of hepatic insufficiency or persistently abnormal liver function tests (three times the upper limit of normal) occur.
• Hypersensitivity: Discontinue at the first appearance of skin rash, mucosal lesions, or any other sign of hypersensitivity.
• Masking Symptoms: Etoricoxib may mask fever and other signs of inflammation.
• Anticoagulants: Exercise caution when co-administering with warfarin or other oral anticoagulants due to potential increased prothrombin time (bleeding risk).

Drug Interactions:

• Oral anticoagulants (e.g., Warfarin): May increase prothrombin time. Close monitoring of INR/prothrombin time is required.
• Diuretics, ACE inhibitors, and Angiotensin II Antagonists: NSAIDs may reduce the effect of these antihypertensive drugs.
• Acetylsalicylic Acid (Aspirin): Can be used concomitantly with low-dose aspirin for cardiovascular prophylaxis, but co-administration increases the risk of GI side effects. High-dose aspirin should be avoided.
• Ciclosporin and Tacrolimus: Co-administration with any NSAID may increase the nephrotoxic effect of these immunosuppressants.
• Lithium: NSAIDs decrease renal excretion of lithium, increasing lithium plasma levels and potential toxicity.
• Food: Can be taken without regard to meals.

Overdose Effects:

• Single doses up to 500 mg and multiple doses up to 150 mg/day for 21 days did not result in significant toxicity.
• Management: In case of overdose, employ usual supportive measures: remove unabsorbed material from the GI tract, clinical monitoring, and symptomatic supportive therapy if required.

Storage Conditions

Store at a temperature of below 30°C, protected from light & moisture. Keep out of reach of children.