Part of the Access Doctor osteoarthritis guide.
Diclofenac Gel for Pain Relief: How to Use It & UK Prescription
A clinically reviewed UK guide to diclofenac gel — how it works, the difference between 1% and 2.32% strengths, how to apply it correctly, which conditions it treats, and how to get it on prescription online.
▶ Key facts
Diclofenac gel is a topical NSAID that penetrates skin and underlying tissue to reduce inflammation at the application site. Because it acts locally rather than systemically, it carries significantly fewer gastrointestinal, renal, and cardiovascular side effects than oral NSAIDs. Available in 1% (Voltarol-equivalent) for OTC and prescription use, and 2.32% (prescription-only) for a higher local concentration. Effective for osteoarthritis of accessible joints, soft tissue injuries, and localised musculoskeletal pain. GPhC pharmacy #9011198.
1%
Standard diclofenac gel strength — OTC and prescription
2.32%
Higher-strength prescription gel — greater local concentration
<10%
Systemic absorption vs oral diclofenac — fewer systemic side effects
3–4×
Daily applications — applied directly to the affected area
What Is Diclofenac Gel?
Diclofenac gel is a topical formulation of diclofenac sodium — a phenylacetic acid NSAID. Rather than being swallowed and distributed systemically through the bloodstream, it is applied directly to the skin overlying the painful area. The active diclofenac penetrates through the skin into the underlying muscle and joint tissue, achieving therapeutically effective local concentrations while maintaining very low systemic blood levels.
How Diclofenac Gel Works
Like all NSAIDs, diclofenac works by inhibiting COX enzymes and reducing prostaglandin synthesis. At the joint or soft tissue level, this reduces the inflammatory mediators causing pain, swelling, and stiffness. The topical route delivers diclofenac directly to the site of inflammation rather than distributing it through the entire body first.
Diclofenac has a slightly greater selectivity for COX-2 over COX-1 compared to naproxen and ibuprofen. COX-2 is the enzyme primarily responsible for inflammation-associated prostaglandins; COX-1 governs gastric protection. This mild selectivity — combined with the low systemic absorption of the topical route — helps explain why topical diclofenac is much less likely to cause GI problems than oral NSAIDs.
To understand NSAID mechanisms in detail — COX-1 vs COX-2 inhibition, pharmacokinetics, and how this compares across NSAIDs: What is naproxen? Mechanism of action guide →
1% vs 2.32%: What Is the Difference?
| Diclofenac 1% gel | Diclofenac 2.32% gel | |
|---|---|---|
| Diclofenac content | 10mg per gram of gel | 23.2mg per gram of gel |
| Availability | OTC (e.g. Voltarol Gel 1%) and prescription | Prescription only |
| Licensed for | Soft tissue injuries, localised MSK pain | Osteoarthritis of superficial joints (knee, ankle, foot, elbow, wrist) |
| Application dose | Typically 2–4g applied 3–4 times daily | Typically 2g applied twice daily (lower frequency, higher concentration) |
| Systemic absorption | Low (<10% of equivalent oral dose) | Slightly higher than 1% due to greater concentration gradient |
What Diclofenac Gel Treats
- Osteoarthritis of superficial joints — knee, ankle, hand, wrist, elbow; diclofenac 2.32% gel has strong evidence for knee OA and is endorsed in NICE guidance for this indication
- Soft tissue sports injuries — sprains, strains, muscle pulls; 1% gel is effective for acute soft tissue injuries in the first 48–72 hours
- Localised musculoskeletal pain — back pain, shoulder pain, neck pain where the affected area is accessible
- Tendinitis and bursitis — superficial tendon and bursa inflammations respond well to topical diclofenac
Diclofenac gel is not appropriate for deep visceral pain, widespread inflammatory disease (systemic rheumatoid arthritis), migraine, period pain, or gout — where oral systemic anti-inflammatories are needed. See naproxen for pain relief for those indications.
How to Apply Diclofenac Gel Correctly
1
Wash and dry your hands
Wash hands before and after applying diclofenac gel to avoid inadvertent transfer to eyes or mucous membranes.
2
Apply to clean, intact skin
Apply only to unbroken skin. Do not use on open wounds, eczema, or dermatitis. The gel should not be applied to mucous membranes or eyes.
3
Measure the correct amount
Follow your prescriber’s or leaflet instructions for the amount per application — typically 2–4g for 1% gel (roughly a 2–4cm strip from the tube).
4
Massage in gently
Gently rub into the affected area. The gel will absorb within a few minutes. Do not cover with an occlusive dressing unless directed.
5
Protect from sun exposure
Avoid direct sunlight or sunlamps on the treated area during treatment and for 2 weeks after — topical diclofenac can increase photosensitivity.
Side Effects and Safety
Because systemic absorption is low, topical diclofenac is much better tolerated than oral NSAIDs for most patients:
- Local skin reactions — dry skin, rash, itching, or a burning sensation at the application site; most common side effect; usually mild and transient
- Photosensitivity — skin at the application site may be more sensitive to sunlight; avoid sun exposure during treatment
- GI effects — rare with topical use; possible with prolonged or large-area application due to cumulative systemic absorption
- Asthma exacerbation — NSAID-sensitive asthma can theoretically be triggered even by topical NSAIDs; use with caution in aspirin-sensitive asthma
Who Should Not Use Diclofenac Gel
- Known NSAID hypersensitivity or aspirin-sensitive asthma
- Third trimester of pregnancy
- Application to broken skin, open wounds, infected skin, or mucous membranes
- Children — check the specific product SPC; most 1% gel products are not recommended under 12–14 years; 2.32% gel is for adults only
Diclofenac Gel vs Oral NSAIDs: When to Use Which
| Diclofenac gel (topical) | Oral NSAID (naproxen/ibuprofen) | |
|---|---|---|
| Systemic side effects | Low — minimal GI, renal, CV risk | Present — GI, renal, CV monitoring important |
| Depth of penetration | Superficial joints and tissues only | Systemic — reaches all sites including deep and visceral |
| Best for | Localised accessible joint/MSK pain; patients who cannot tolerate oral NSAIDs | Widespread inflammatory disease; inaccessible sites; gout; period pain |
| PPI required? | Generally not | Recommended |
| NICE recommendation for knee OA | First-line topical NSAID (endorsed) | Second-line if topical insufficient |
Getting Diclofenac Gel in the UK
Diclofenac 1% gel (Voltarol Gel) is available OTC from UK pharmacies. Prescription diclofenac 2.32% gel requires a clinical assessment. Access Doctor can prescribe diclofenac gel following a short online consultation.
Get Diclofenac Gel Prescribed Online
Prescription diclofenac gel following a short online clinical consultation. GPhC-registered pharmacist independent prescribers. Discreet next-day delivery. GPhC pharmacy #9011198.
Start Consultation →Frequently Asked Questions
What is diclofenac gel used for?
Diclofenac gel is used for localised musculoskeletal pain including osteoarthritis of accessible joints (knee, hand, wrist, elbow), soft tissue injuries (sprains, strains), tendinitis, and bursitis. It is not suitable for systemic inflammatory conditions, period pain, gout, or deep-seated pain.
What is the difference between diclofenac 1% and 2.32% gel?
Diclofenac 1% gel (equivalent to Voltarol Gel) is available both OTC and on prescription, mainly for soft tissue injuries and localised MSK pain. Diclofenac 2.32% gel is prescription-only and provides a higher local concentration, primarily licensed for osteoarthritis of superficial joints. The 2.32% formulation is applied less frequently (twice daily vs 3–4 times for 1%).
Is diclofenac gel safer than oral NSAIDs?
For most patients, yes. Because topical diclofenac has very low systemic absorption (<10% of an equivalent oral dose), it carries much lower risk of gastrointestinal, renal, and cardiovascular side effects than oral NSAIDs. Local skin reactions are the most common side effect.
Can I use diclofenac gel in pregnancy?
Diclofenac gel is contraindicated in the third trimester of pregnancy. Use with caution in the first and second trimesters and only if considered essential by a clinician. Always inform your prescriber or pharmacist if you are pregnant.
Does diclofenac gel need a prescription in the UK?
Diclofenac 1% gel (Voltarol Gel) is available OTC at UK pharmacies for soft tissue injuries. Prescription diclofenac 2.32% gel requires a prescription. Access Doctor can provide prescriptions for both following an online clinical consultation.
References
- NICE. Osteoarthritis: care and management. CG177. 2014 (updated 2022).
- NICE CKS. Sprains and strains. Updated 2022.
- NHS. Diclofenac. nhs.uk/medicines/diclofenac
- BNF. Diclofenac sodium (topical). bnf.nice.org.uk
Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting or changing any treatment. In a medical emergency, call 999.