Diclofenac
In stock
50mg · 100mg
from 29,58 £
In brief
Diclofenac belongs to the non-steroidal anti-inflammatory drug group. By reducing inflammation, it can ease pain and stiffness associated with joint and muscle conditions.
Basic diclofenac information and regulatory status
| Attribute | Details |
|---|---|
| International Nonproprietary Name (INN) | Diclofenac |
| Common UK brands | Voltarol; generic diclofenac sodium and diclofenac potassium |
| Available forms | Tablets (gastro-resistant/extended-release), gel, sprays, plasters, injections |
| Leading manufacturers | Novartis and Haleon (Voltarol), Teva, Mylan |
| Regulatory approval | MHRA authorised |
| Classification | Prescription-only (tablets/injections); pharmacy or general sale medicines (topical) |
Diclofenac is widely available across the United Kingdom through brands like Voltarol tablets and topical gels. The Medicines and Healthcare products Regulatory Agency approves multiple formulations, recognising its efficacy in pain relief regimens. Oral forms like gastro-resistant tablets require prescription due to potential systemic effects, while topical preparations fall under pharmacy supervision.
Pharmacology and mechanism of action
Diclofenac functions as a potent cyclooxygenase (COX) inhibitor, targeting both COX-1 and COX-2 enzyme pathways. By blocking prostaglandin synthesis at inflammation sites, it reduces pain signals and swelling. Hepatic cytochrome P450 enzymes metabolise approximately 50% of oral tablets within 30-60 minutes of consumption, while renal pathways excrete metabolites post-digestion.
Food interactions influence bioavailability: high-fat meals delay absorption. Alcohol consumption exacerbates gastrointestinal risks by compromising mucosal protection. The topical gel formulations minimise systemic exposure by acting locally at application sites through skin penetration restrictions.
Approved indications and uses
In the UK, diclofenac is licensed for inflammatory joint diseases including osteoarthritis, rheumatoid arthritis, and acute gout flares. Following NHS guidance, clinicians routinely prescribe it for musculoskeletal pain like lower back pain or sports injuries where inflammation drives discomfort.
Diclofenac is also used for postoperative pain and renal colic. Treatment should be reviewed regularly, using the lowest effective dose for the shortest possible time.
Special populations and off-label applications
Use in children is limited to specific indications under specialist guidance. Consultants exercise caution when treating elderly individuals by initiating low-dose regimens due to renal impairment risks. Expectant mothers must avoid diclofenac in the third trimester, while breastfeeding patients generally utilise topical alternatives.
Fast-acting diclofenac potassium tablets are also used for migraine attacks, and dental practitioners sometimes prescribe short courses for postoperative tooth pain relief.
Standard dosage and forms
Diclofenac comes in different forms, each with specific dosing suitable for particular conditions. Oral tablets typically come as 50mg taken two to three times daily for osteoarthritis, while Voltarol gel requires applying 2-4 grams to affected joints up to four times daily. For severe flare-ups, healthcare providers might recommend a one-time 75mg injection.
Doctors select the form based on symptom severity and location:
| Condition | Standard adult dose |
|---|---|
| Chronic joint pain (knees, hands) | Sustained-release tablets: 75–100mg once daily |
| Acute muscle strain | Topical gel: apply 4g 4x/day |
| Post-surgery/dental pain | Single IM injection: 75mg |
| Eye inflammation | Eye drops: One drop 4x daily (without touching bottle to eye) |
Gastro-resistant tablets must be swallowed whole while gels require massaging in until fully absorbed. Using higher amounts doesn’t increase pain relief but raises side effect risks.
Dosage adjustments and administration
When your kidneys or liver aren’t working at full capacity, diclofenac doses often get reduced due to slower medication processing. Doctors might halve the standard amount or recommend alternative treatments entirely in cases of severe impairment. The elderly usually start with minimal strengths like 25mg tablets even without organ issues.
For administration:
- Swallow gastro-resistant tablets whole – never crush or chew
- If a dose gets forgotten, take it unless nearly time for the next dose
- Storage below 30°C keeps tablets effective; avoid humid bathrooms
- Transit requires carrying medicines in original packaging
- Topical forms perform best when applied to clean, dry, unbroken skin
People experiencing persistent abdominal discomfort should stop use immediately since this might indicate developing gastrointestinal complications.
Contraindications and precautions
Diclofenac poses serious dangers if taken by those with specific underlying conditions. Absolute contraindications mean doctors should never prescribe the medication in these situations:
– Active stomach ulcers or gastrointestinal bleeding history
– Established heart failure (NYHA class II–IV), ischaemic heart disease, cerebrovascular disease or recent bypass surgery
– Confirmed allergic reactions to aspirin or NSAIDs
– Third-trimester pregnancy
– Established heart failure (NYHA class II–IV), ischaemic heart disease, cerebrovascular disease or recent bypass surgery
– Confirmed allergic reactions to aspirin or NSAIDs
– Third-trimester pregnancy
Significant precautions exist for people with:
Controlled hypertension requiring vigilant blood pressure checks
Mild kidney impairment necessitating regular renal function testing
Anticoagulant users facing elevated bleeding dangers
Crohn’s disease or ulcerative colitis patients at relapse risk
Mild kidney impairment necessitating regular renal function testing
Anticoagulant users facing elevated bleeding dangers
Crohn’s disease or ulcerative colitis patients at relapse risk
The Medicines and Healthcare products Regulatory Agency (MHRA) warns all NSAIDs carry cardiovascular threats – particularly concerning for smokers, diabetics, or those with existing heart conditions. Discussion of alternative pain relief becomes essential for these patients despite lacking absolute restrictions.
Side effects and risk management
Most diclofenac issues start mildly but may progress to dangerous complications with prolonged usage. Frequent discomfort includes indigestion, headaches, and temporary skin reactions at gel application sites. These typically don’t require stopping treatment unless persistent.
More critical concerns demanding urgent medical help are:
Dark, tarry stools signalling internal bleeding
Severe stomach pain or vomiting blood
Unexplained tiredness with yellow skin/loss of appetite indicating liver distress
Significant ankle swelling and breathing difficulties suggesting failing kidneys or heart
Severe stomach pain or vomiting blood
Unexplained tiredness with yellow skin/loss of appetite indicating liver distress
Significant ankle swelling and breathing difficulties suggesting failing kidneys or heart
Regular monitoring of liver and kidney function is advisable during long-term treatment. Preventive strategies include:
– Using lowest effective dose for shortest duration
– Combining with stomach protectors like omeprazole for high-risk patients
– Switching to naproxen or ibuprofen when long-term anti-inflammatories are required
– Avoiding simultaneous alcohol/corticosteroid usage increasing ulcer formation likelihood
Stopping treatment usually resolves minor reactions within days while critical complications necessitate emergency intervention.
– Combining with stomach protectors like omeprazole for high-risk patients
– Switching to naproxen or ibuprofen when long-term anti-inflammatories are required
– Avoiding simultaneous alcohol/corticosteroid usage increasing ulcer formation likelihood
Stopping treatment usually resolves minor reactions within days while critical complications necessitate emergency intervention.
Comparison of alternatives (UK)
Common alternatives vary in their properties:
| Drug | Relative efficacy | Safety profile |
|---|---|---|
| Diclofenac | Strong anti-inflammatory | Higher CV/GI risk |
| Ibuprofen | Moderate pain relief | Lower CV risks |
| Naproxen | Longer duration | Intermediate risk |
| Paracetamol | Mild analgesia | No GI irritation |
Diclofenac exhibits superior anti-inflammatory potency but carries greater cardiovascular risks than ibuprofen. Unlike paracetamol, it treats inflammation rather than just symptoms. Naproxen, with 12-hour dosing, is often chosen where a lower cardiovascular risk is needed.
