Naproxen: Uses, Dosage, Side Effects, and More
1. Drug Name
Generic Name: Naproxen
Brand Name(s):
- Pakistan: Naprosyn, Naxopren
- India: Naprosyn, Naprosyn EC
- United States: Aleve, Anaprox
- United Kingdom: Feminax Ultra, Naprosyn
2. Pharmacological Class
Class: Nonsteroidal Anti-inflammatory Drug (NSAID)
Subclass: Propionic Acid Derivative
3. Mechanism of Action
Naproxen works by inhibiting the enzymes cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), which are responsible for the synthesis of prostaglandins. Prostaglandins are hormone-like substances that are involved in inflammation, pain, and fever. By inhibiting these enzymes, naproxen reduces pain, inflammation, and fever.
4. Indications
Primary Indications:
- Relief of mild to moderate pain (e.g., headache, dental pain, menstrual cramps, muscle pain).
- Management of inflammatory conditions such as arthritis (rheumatoid arthritis, osteoarthritis).
- Reduction of fever.
Off-label Uses: Prevention of migraine headaches.
5. Dosage and Administration
Standard Dosage:
- Adults (for pain and inflammation): 250 mg to 500 mg twice daily. Maximum dose should not exceed 1500 mg per day.
- Adults (for osteoarthritis): 500 mg to 1000 mg per day in two divided doses.
- Route of Administration: Oral (tablets, delayed-release tablets).
Special Populations:
- Pediatric: Safety and effectiveness in children have not been established.
- Geriatric: Use lower doses to avoid adverse effects, particularly gastrointestinal effects and renal impairment.
6. Pharmacokinetics
Absorption: Naproxen is well absorbed from the gastrointestinal tract.
Distribution: It is extensively bound to plasma proteins.
Metabolism: It undergoes hepatic metabolism to inactive metabolites.
Excretion: It is excreted primarily in urine as unchanged drug and metabolites.
Half-life: Approximately 12-15 hours.
7. Contraindications
Naproxen is contraindicated in patients with a history of hypersensitivity to naproxen or other NSAIDs, and in patients with active peptic ulcer disease or a history of gastrointestinal bleeding.
8. Warnings and Precautions
Use with caution in patients with a history of cardiovascular disease, renal impairment, or hepatic impairment.
Long-term use of naproxen may increase the risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke.
9. Side Effects
Common Side Effects: Upset stomach, heartburn, and abdominal pain.
Serious Side Effects: Gastrointestinal bleeding, renal toxicity, and hypersensitivity reactions.
10. Drug Interactions
Major Interactions: Anticoagulants (warfarin), antiplatelet drugs (aspirin), selective serotonin reuptake inhibitors (SSRIs).
Moderate Interactions: Diuretics, angiotensin-converting enzyme (ACE) inhibitors, and lithium.
Minor Interactions: Alcohol and certain antihypertensive drugs.
11. Pregnancy and Lactation
Pregnancy Category: Naproxen is not recommended during the third trimester of pregnancy due to potential risks to the fetus.
Breastfeeding Considerations: Naproxen is excreted in breast milk. Use caution during breastfeeding, and consult with a healthcare provider for advice.
12. Patient Counseling Information
Key Points for Patients:
- Take naproxen exactly as directed by your healthcare provider.
- Do not take naproxen with other NSAIDs or aspirin unless directed by your doctor.
- Report any signs of gastrointestinal bleeding, such as black, tarry stools, to your doctor immediately.
Administration Tips:
- Take naproxen with food or milk to minimize stomach upset.
- Swallow delayed-release tablets whole; do not crush or chew.