Naxo250 mg

Naxo is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, reduce fever, and control inflammation. Indications are classified below by strength of evidence.

Established / FDA-approved uses

• Osteoarthritis
• Rheumatoid arthritis
• Ankylosing spondylitis
• Juvenile idiopathic arthritis (pediatric, weight-based dosing)
• Acute painful shoulder (bursitis/tendinitis)
• Acute gouty arthritis
• Primary dysmenorrhea
• Mild-to-moderate acute pain (musculoskeletal injury, postoperative pain, headache/migraine)

Guideline-supported / commonly used uses

• Fever reduction (antipyretic use)
• Tension-type headache and acute migraine attack (often as adjunct or when first-line agents are insufficient)

Naxo is not an antibiotic and has no role in treating infections.

Each tablet contains Naproxen Sodium INN as the active ingredient, commonly available in strengths of 250 mg, 275 mg, 500 mg, and 550 mg. Sustained-release/controlled-release tablets (typically 500 mg) and an oral suspension (125 mg/5 mL, expressed as naproxen equivalent) are also marketed. Excipients vary by manufacturer.

Naxo is the sodium salt of naproxen, a propionic acid derivative NSAID. The sodium salt form dissolves and is absorbed more rapidly than naproxen base, giving faster onset of pain relief while retaining naproxen's comparatively long duration of action, which allows less frequent dosing than many other NSAIDs.

It is widely used for short-term relief of acute pain and fever, and for longer-term management of chronic inflammatory joint conditions, under medical supervision.

Naxo belongs to the Non-Steroidal Anti-Inflammatory Drug (NSAID) class, specifically the propionic acid derivative group. It is a non-selective cyclooxygenase (COX-1 and COX-2) inhibitor.

Naproxen Sodium works by non-selectively inhibiting cyclooxygenase (COX-1 and COX-2) enzymes, reducing the synthesis of prostaglandins that mediate pain, inflammation, and fever. Inhibition of COX-1 also accounts for its gastrointestinal and antiplatelet effects.

After oral administration, the sodium salt is absorbed rapidly, producing peak plasma concentrations sooner than naproxen base. Naproxen is highly protein-bound (>99%), has a relatively long elimination half-life of approximately 12-17 hours (which supports twice-daily dosing), and is metabolized in the liver with excretion mainly in urine.

Naxo tablets should be swallowed whole with a full glass of water, preferably taken with food, milk, or an antacid to reduce gastrointestinal upset. Sustained/controlled-release tablets must not be crushed, split, or chewed. The oral suspension should be shaken well before measuring each dose with an appropriate measuring device. Do not lie down for at least 10 minutes after taking a dose.

Clinically significant interactions with Naxo include:

• Anticoagulants (e.g. warfarin) and other NSAIDs/aspirin: additive antiplatelet and GI mucosal effects increase risk of serious bleeding.
• Low-dose aspirin: Naxo may interfere with aspirin's antiplatelet (cardioprotective) effect and increases GI complication risk when combined.
• ACE inhibitors, ARBs, and diuretics: Naxo can blunt their antihypertensive/natriuretic effect and, in combination, raises the risk of acute kidney injury (the "triple whammy" effect), especially in volume-depleted or elderly patients.
• Lithium: reduced renal clearance of lithium, risking lithium toxicity.
• Methotrexate: reduced renal clearance of methotrexate, increasing risk of toxicity, particularly at higher methotrexate doses.
• SSRIs/SNRIs and corticosteroids: additive risk of GI bleeding/ulceration when combined with Naxo.
• Cyclosporine: increased risk of nephrotoxicity.

Common side effects of Naxo include dyspepsia, heartburn, abdominal pain, nausea, constipation or diarrhea, headache, dizziness, drowsiness, tinnitus, and fluid retention/edema.

Serious but less common effects include gastrointestinal bleeding/ulceration/perforation, cardiovascular thrombotic events (myocardial infarction, stroke), renal impairment, elevated liver enzymes/hepatotoxicity, hypertension, hyperkalemia, aseptic meningitis, and severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis) or anaphylactoid reactions. Seek urgent medical care for signs such as black/bloody stools, chest pain, sudden weakness, jaundice, or severe rash.

Pregnancy: Naxo should be avoided starting at approximately 20 weeks of gestation, as NSAIDs at this stage can cause fetal renal dysfunction leading to oligohydramnios. Use at or after about 30 weeks (third trimester) is contraindicated due to risk of premature closure of the fetal ductus arteriosus and other fetal/neonatal complications. Earlier in pregnancy, Naxo should be used only if clearly needed, at the lowest effective dose for the shortest duration, and only after consulting a physician, as safety has not been definitively established.

Lactation: Naproxen passes into breast milk in small amounts (roughly 1% of maternal plasma levels). Because of the potential for adverse effects in a nursing infant, Naxo should be used during breastfeeding only if a physician determines the benefit outweighs the risk; a shorter-acting NSAID is often preferred by clinicians for breastfeeding mothers.

Cardiovascular risk: Naxo, like other NSAIDs, carries a boxed-warning-level risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal; this risk may increase with duration of use and in patients with existing cardiovascular disease or risk factors.

Gastrointestinal risk: Increased risk of serious GI adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can occur at any time and without warning symptoms, particularly in elderly patients or those with prior peptic ulcer disease/GI bleeding.

Renal effects: May cause renal papillary necrosis or other renal injury, especially in patients with pre-existing renal impairment, heart failure, liver dysfunction, volume depletion, or in the elderly; monitor renal function.

Hepatic effects: Rare but potentially severe hepatotoxicity (elevated transaminases, hepatitis) has been reported; discontinue if signs of liver dysfunction develop.

Other: May cause fluid retention, edema, and hypertension or worsen existing hypertension/heart failure; use with caution in asthma (risk of bronchospasm); avoid use for perioperative pain in the setting of CABG surgery (see Contraindications).

Symptoms of Naxo overdose may include drowsiness, dizziness, nausea, vomiting, epigastric pain, gastrointestinal bleeding, and, in severe cases, hypotension, respiratory depression, acute kidney injury, coma, or seizures.

Overdose is a medical emergency. Seek immediate medical attention or contact emergency services/a poison control center. Treatment is supportive and symptomatic; there is no specific antidote. Do not attempt home treatment beyond seeking urgent professional care.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

Renal impairment

Use Naxo with caution and at the lowest effective dose in mild-to-moderate renal impairment; avoid in advanced/severe renal disease unless no alternative exists, and monitor renal function closely.

Hepatic impairment

Use the lowest effective dose in mild-to-moderate hepatic impairment; avoid in severe hepatic impairment.

Elderly

Elderly patients are at greater risk of serious GI, cardiovascular, and renal adverse effects with Naxo; use the lowest effective dose for the shortest duration and monitor closely.

Pediatric

See Pediatric Uses below.

Naxo should be used at the lowest effective dose for the shortest duration consistent with the treatment goal, due to dose- and duration-related cardiovascular and gastrointestinal risks. For acute pain, fever, or dysmenorrhea, use is typically limited to a few days; for chronic conditions such as osteoarthritis or rheumatoid arthritis, longer-term use requires periodic medical review of continued need, effectiveness, and tolerability.

Nonsteroidal Anti-Inflammatory Drug (NSAID); propionic acid derivative; non-selective COX-1/COX-2 inhibitor.

Naproxen Sodium exerts its analgesic, antipyretic, and anti-inflammatory effects primarily through reversible, non-selective inhibition of cyclooxygenase (COX-1 and COX-2), thereby decreasing the peripheral synthesis of prostaglandins involved in pain, fever, and the inflammatory response.

C (Category D if used at approximately 30 weeks gestation or later)

Naxo (as the oral suspension, dosed by body weight) is approved for the treatment of polyarticular juvenile idiopathic arthritis in children, typically dosed at approximately 10 mg/kg/day in two divided doses. Tablet formulations are generally not recommended for children weighing less than 50 kg because appropriate dose reduction is not possible.

Safety and efficacy of Naxo for indications other than juvenile idiopathic arthritis, and for children under 2 years of age, have not been established. Use in children should be under close medical supervision, with attention to growth, renal function, and GI tolerability given long-term use in this population.