Mechanism of action

It is a non-steroidal anti-inflammatory drug (NSAID) that works by blocking the production of prostaglandins, chemicals in the body that cause inflammation and pain. Its action inhibits cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2. By inhibiting these enzymes, naproxen reduces the production of prostaglandins and thus reduces inflammation and pain

Spectrum

The spectrum of naproxen activity includes treating pain, inflammation, and fever. It is commonly used to treat rheumatoid arthritis, osteoarthritis, gout, and menstrual cramps. It can also alleviate pain caused by injuries, such as sprains and strains, and reduce fever

DRUG INTERACTION

Contraindicated  

Serious Use Alternative  

Monitor Closely  

Minor  

Frequency defined:

1-10%

Constipation

Drowsiness

Heart burn

Edema

GI perforation

GI ulcers

Diarrhea

Diverticulitis

Hearing disturbances

Abdominal pain

Dizziness

Headache

Nausea

GI bleeding

Lightheadedness

Fluid retention

Stomatitis

Dyspnea

Black box warning

It is a non-steroidal anti-inflammatory drug (NSAID), carries a black box warning for an increased heart attack or stroke risk. This warning is the most severe from the U.S. Food and Drug Administration (FDA) and indicates that the drug may cause severe or life-threatening side effects.

Patients taking naproxen should talk to their healthcare provider about the potential risks and benefits of the medication and follow the recommended dosage and duration of use.

Contraindications

• Hypersensitivity to naproxen or any other ingredient in the medication
• Active peptic ulceration or a history of peptic ulceration
• Hemophilia or other bleeding disorders
• Severe heart failure or renal failure
• The third trimester of pregnancy
• Children under 12 years of age
• Concomitant use of oral anticoagulants or other medications that increase the risk of bleeding

Caution

• Gastrointestinal bleeding: It may increase the risk of gastrointestinal bleeding, especially in older adults or those with a history of ulcers or gastrointestinal bleeding.
• Cardiovascular and cerebrovascular risks: Long-term use of naproxen may increase the risk of cardiovascular and cerebrovascular events.
• Renal impairment: It should be used with caution in patients with renal impairment, as it may accumulate in the body and cause toxicity.
• Hepatic impairment: It should be used cautiously in patients with hepatic impairment.
• Anemia: It may cause anemia, particularly in patients who are already at risk for anemia, such as those with a history of bleeding or a deficiency in iron or vitamin B12.
• Pregnancy and breastfeeding: It should be used during pregnancy and breastfeeding only if the potential benefits outweigh the potential risks.
• Interactions with other medications: It may interact with other medications, including blood thinners, anti-platelet medications, and corticosteroids.

Pregnancy consideration: Insufficient data available

Lactation: Excretion of the drug in human breast milk is unknown

Pregnancy category:

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester.

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.

Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.

Category N: There is no data available for the drug under this category

Pharmacology

It is a non-steroidal anti-inflammatory drug (NSAID) that inhibits the synthesis of prostaglandins in body tissues. Prostaglandins are chemicals that play a crucial role in inflammation, pain, and fever. Naproxen is an NSAID that works by inhibiting the activity of two enzymes, COX-1 and COX-2, which are responsible for the production of prostaglandins. By inhibiting the activity of these enzymes, Naproxen reduces the synthesis of prostaglandins and thereby reduces inflammation, pain, and fever. Naproxen may also have anti-inflammatory effects by inhibiting chemotaxis, altering lymphocyte activity, decreasing pro-inflammatory cytokine activity, and inhibiting neutrophil aggregation.

Pharmacodynamics

Inhibition of prostaglandin synthesis: It is a non-selective COX inhibitor, which inhibits the activity of both COX-1 and COX-2 enzymes. These enzymes are responsible for the production of prostaglandins, which play a crucial role in inflammation, pain, and fever. By inhibiting the activity of these enzymes, Naproxen reduces the synthesis of prostaglandins and thereby reduces inflammation, pain, and fever.

Anti-inflammatory effects: It has anti-inflammatory effects by inhibiting the activity of several mediators of inflammation, such as leukotrienes, and by reducing the production of pro-inflammatory cytokines.

Analgesic effects: It acts as an analgesic by reducing the synthesis of prostaglandins, which are involved in transmitting pain signals in the body.

Antipyretic effects: It has antipyretic effects by reducing the production of prostaglandins, which regulate body temperature.

Platelet inhibition: It has a weak anti-platelet effect by inhibiting the production of thromboxane A2, a prostaglandin involved in platelet aggregation.

Pharmacokinetics

Absorption

The absorption of the medication is 95% bioavailable, with an onset of 30-60 minutes and a duration of fewer than 12 hours. The peak serum time for tablets is 1-4 hours; for delayed release on an empty stomach, it is 2-12 hours, and for delayed release with food, it is 4-24 hours. The peak plasma concentration is 62-96 mcg/mL

Distribution

The drug is mostly protein bound at less than 99%. The volume of distribution is 0.16 L/kg.

Metabolism

It is metabolized in the liver via conjugation, with 6-Desmethylnaproxen and glucuronide conjugates as metabolites. The enzymes COX-1 and COX-2 are inhibited.

Elimination/excretion

The half-life is 12-17 hours and is not dialyzable. The clearance of the medication is 0.13 mL/min/kg, and it is excreted mainly in the urine (95%) and, to a lesser extent, in the feces (<3%)

Administration

It is typically administered orally in the form of tablets or capsules. The recommended dosage will vary depending on the treated condition and the individual’s response to the medication. It is usually taken every 8-12 hours with food to reduce the risk of stomach upset.

Patient information leaflet

Generic Name: naproxen

Pronounced: [ na-PROX-en ]

Why do we use naproxen?

It is a non-steroidal anti-inflammatory drug (NSAID) used to relieve pain, reduce inflammation, and lower fever. It is used to treat a wide range of conditions, including:

• Osteoarthritis and rheumatoid arthritis
• Ankylosing spondylitis
• Tendinitis and bursitis
• Gout
• Menstrual cramps
• Acute pain, such as that caused by a toothache or injury
• Migraine and other types of headaches