Synflex Tablet Uses, Dosage and Side Effects in Pakistan

What Is Synflex?

Synflex is the brand name for naproxen sodium — the sodium salt of naproxen that absorbs faster than plain naproxen. It is an NSAID (non-steroidal anti-inflammatory drug) that blocks prostaglandins, the chemicals that cause pain and inflammation. Unlike Brufen (ibuprofen), which lasts 6 hours, Synflex provides 8–12 hours of relief, so two doses daily are usually enough.

Synflex Tablet Uses

1. Musculoskeletal Pain and Muscle Injuries

Sports injuries, sprains, strains, and overuse injuries.

2. Arthritis and Joint Pain

Osteoarthritis, rheumatoid arthritis, and gout flares.

3. Menstrual Cramps (Dysmenorrhea)

Very effective for period pain — reduces prostaglandins that cause cramps. Start 1–2 days before expected onset for best results.

4. Dental and Toothache Pain

Used by dentists post-procedure and for toothache relief.

5. Back Pain and Neck Pain

Acute and chronic musculoskeletal pain in the spine and neck.

6. Headache and Migraine

Can relieve both tension headache and migraine headache.

7. Fever (Secondary)

Has an antipyretic effect, though paracetamol is preferred for fever alone.

8. Post-Surgical Pain

Used after minor procedures for pain management.

Dosage

Synflex vs Brufen — Key Differences

Side Effects

Common:

• Stomach upset, nausea, heartburn
• Headache, dizziness
• Fluid retention (mild ankle swelling)
• Drowsiness

Serious:

• GI bleeding / peptic ulcer — the main risk with long-term use
• Kidney damage — at high doses or with dehydration
• Cardiovascular risk — increased heart attack/stroke risk with chronic use
• Allergic reaction — rash, swelling, difficulty breathing
• Liver toxicity — rare

Warning Signs — Stop and See a Doctor

• Black/tarry stools or blood in vomit (GI bleed)
• Sudden severe chest pain (cardiac event)
• Swelling of face/lips/throat (allergy)
• Significant reduction in urine output (kidney damage)
• Yellowing of eyes/skin (liver)

Who Should NOT Take Synflex

• Active peptic ulcer or GI bleeding
• Severe kidney disease (GFR < 30)
• Severe liver disease
• Heart failure
• Third trimester of pregnancy (closes fetal ductus arteriosus)
• Aspirin-sensitive asthma (may cross-react)
• Allergy to any NSAID
• Children under 12 years

Stomach Protection

Adding a PPI (Risek 20, Pantop) is recommended when:

• Age over 60
• Taking for more than 7 days
• Taking blood thinners (aspirin, warfarin) simultaneously
• Previous history of peptic ulcer
• Concurrent steroid use

Drug Interactions

• Aspirin / Loprin: Avoid combining — doubles GI bleeding risk and reduces each other's effectiveness
• Warfarin: Increased bleeding risk — INR monitoring needed
• Lithium: Naproxen increases lithium levels — toxicity risk
• ACE inhibitors / ARBs: Reduced blood pressure control, kidney risk
• Diuretics: Reduced diuretic effect
• Methotrexate: Toxicity risk
• SSRIs: Increased GI bleeding risk

Use in Special Situations

• Pregnancy: Safe in first and second trimester (short-term only); strictly avoid in third trimester
• Breastfeeding: Avoid; passes into breast milk
• Elderly (60+): Use lowest effective dose + PPI; kidneys are more vulnerable
• Dengue patients: NEVER use NSAIDs in dengue — risk of haemorrhage; use paracetamol only

Pakistan Brands of Naproxen Sodium

• Synflex 275 mg / 550 mg (Sami Pharma)
• Atrosan 275 mg / 550 mg
• Naprosyn (plain naproxen, not sodium salt — slightly slower)
• Generic naproxen sodium

Conclusion

Synflex (naproxen sodium) is one of Pakistan's most reliable painkillers — longer-acting than Brufen and effective for joint pain, period cramps, and musculoskeletal injuries. However, it carries real GI, kidney, and cardiac risks, especially with long-term use. Always take with food, avoid in kidney disease and peptic ulcer, and add a PPI if taking for more than a week. Use Ilaaj AI for a proper diagnosis and personalised pain management plan.