Diclofenac: History, Side Effects, and Changing Role (Especially in India)

1. Brief History – When Was Diclofenac Invented?

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID). It was:

• Developed by a pharmaceutical company (Ciba-Geigy, now part of Novartis) in the 1960s.
• Introduced into medical use in the early 1970s in many countries.

At that time, it was seen as a strong and effective painkiller and anti-inflammatory medicine, similar in “family” to drugs like ibuprofen and indomethacin.

2. Why Were Side Effects Not Fully Understood in the Beginning?

When new drugs are introduced, safety is checked in:

• Small clinical trials (limited number of patients, limited duration).
• Selected patient groups (often excluding very elderly people, those with kidney/heart disease, and those on many other medicines).

Because of this:

• Common and short-term side effects (like acidity, nausea) are detected early.
• Rare or long-term problems (like heart attacks, strokes, severe kidney damage) may not appear until millions of people worldwide have used the drug over many years.

For diclofenac, as with many NSAIDs, the full extent of:

• Gastrointestinal risk (ulcers, bleeding),
• Kidney effects,
• Cardiovascular risk (heart attack, stroke),

became clearer only after long-term, post-marketing experience and large population studies.

3. Why Has Diclofenac Been Used So Widely in India for So Long?

Diclofenac became extremely popular in India for several reasons:

• Effective and fast-acting for many types of pain – musculoskeletal pain, arthritis, post-operative pain, menstrual pain, etc.
• Low cost – generic versions made it very affordable compared with some alternatives.
• Multiple dosage forms – tablets, slow-release tablets, injections, gels, eye drops, etc.
• Prescription and quasi–over-the-counter use – in practice, many people obtained it easily from pharmacies, sometimes without proper medical supervision.
• Heavy promotion and familiarity – doctors, pharmacists, and patients became used to it over decades, so it became the “default” painkiller for moderate to severe pain.

In addition, in India:

• There has historically been high use of injectable diclofenac in clinics and small hospitals for quick pain relief.
• Veterinary diclofenac was used in cattle, which later was linked to a serious decline in vulture populations, leading to bans/restrictions in veterinary use (this is about wildlife safety, not human use, but it affected the overall image of diclofenac).

4. What Side Effects Became a Concern Later?

4.1 Gastrointestinal (Stomach and Intestine)

• Acidity, gastritis.
• Peptic ulcers.
• Bleeding in the stomach or intestines (which can be serious and sometimes life-threatening).

4.2 Kidney (Renal) Effects

• Reduction in kidney blood flow, especially in people with existing kidney disease, dehydration, heart failure, or on certain medications (e.g., ACE inhibitors, diuretics).
• Potential worsening of chronic kidney disease.

4.3 Cardiovascular (Heart and Blood Vessels)

• Increased risk of heart attack and stroke with long-term use or higher doses, particularly in people with existing heart disease or risk factors (hypertension, diabetes, smoking, high cholesterol, etc.).
• Some large studies suggested diclofenac may carry cardiovascular risks similar to or higher than some other NSAIDs.

4.4 Other Concerns

• Liver enzyme elevations in some patients.
• Rare but serious skin reactions or allergic reactions.

These are known class effects of NSAIDs, but patterns and risk levels differ among individual drugs.

5. “Now Why No More Useful?” – What Has Actually Changed?

It is not that diclofenac is “no more useful” – it still works for pain and inflammation. What has changed is the balance between benefit and risk in the light of newer safety data and the availability of alternative options.

5.1 Current Thinking (General)

• Diclofenac is still used, but doctors are now more careful about:

  • Using the lowest effective dose for the shortest possible duration.
  • Avoiding or limiting it in people with high cardiovascular risk or severe kidney disease.
  • Co-prescribing gastroprotective measures (like PPIs) in high GI-risk patients, if an NSAID is necessary.

• Many guidelines now prefer other NSAIDs (e.g., naproxen in some cardiovascular-risk situations) or paracetamol for mild pain when appropriate.

5.2 In India Specifically

In India, diclofenac is:

• Still available and commonly prescribed, but with more awareness of its risks.
• Veterinary use (especially multi-dose vials) has been restricted/banned because of the vulture crisis, not because it “stopped working” in humans.
• Under greater scrutiny regarding dose, duration, and patient selection, similar to other countries.

So, it is not that diclofenac “no longer works” – the issue is that:

• We now understand its side-effect profile much better.
• Regulators and doctors are more cautious.
• Safer or equally effective alternatives may be preferred for many patients, especially those with heart or kidney risk.

6. Why It Felt Like “No One Understood Side Effects” Earlier

A few reasons:

• Limited early data: Smaller trials cannot detect rare but serious events.
• Underreporting: Adverse events were underreported or not always linked back to the drug.
• Lack of awareness among the public: Many people saw it as a routine painkiller, similar to paracetamol, and were unaware of long-term risks.
• Over-the-counter–like use: Easy availability led to long-term, unsupervised use, which increased complications.

7. Key Takeaways for You

• Diclofenac is an effective NSAID but has important risks, especially for the stomach, kidneys, and heart.
• It became widely used in India because it was cheap, effective, and very familiar to doctors and patients.
• Newer evidence has not made it “useless,” but it has made doctors more careful about who uses it, how much, and for how long.
• Any decision to use or avoid diclofenac should be made with a doctor, based on your individual health conditions and risk factors.

8. What You Can Discuss With Your Doctor

If you or a family member has been taking diclofenac, you can ask your doctor:

• Is diclofenac the safest option for my heart, kidneys, and stomach?
• Are there alternative pain medicines that might be safer for me?
• Do I need any tests (kidney function, etc.) if I’ve used diclofenac long term?
• What is the lowest effective dose and shortest duration suitable for me?

For educational and informational purposes only. Not a diagnosis or medical advice. Please consult a licensed healthcare professional.

This is general drug information — do not self-medicate. Consult your doctor for personalized medical advice.

If you need more help, I’m here to assist. For medical concerns, always consult a licensed healthcare professional.