Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID). Side effects can vary by form (oral tablet, delayed-release, diclofenac potassium, topical gel/patch) and individual health. Here’s a general overview.
Common, usually mild side effects (often improve with time or with food):
- Upset stomach, indigestion, heartburn
- Nausea, vomiting
- Diarrhea or constipation
- Gas, abdominal discomfort
- Dizziness or headache
- Mild skin reactions with topical forms (rash, itching)
Less common but possible:
- Swelling or fluid retention (edema), high blood pressure
- Tinnitus (ringing in the ears)
- Drowsiness or fatigue
- Dry mouth
Less common but serious (seek medical care promptly):
- Signs of allergic reaction: hives, facial swelling, severe dizziness, trouble breathing
- Gastrointestinal bleeding or ulcers: black/tarry stools, vomiting blood, severe stomach pain
- Serious liver injury: yellowing of the skin or eyes, dark urine, pale stools
- Kidney problems: reduced urine, swelling, shortness of breath
- Heart attack or stroke symptoms: chest pain, weakness on one side, trouble speaking, sudden severe headache
- Severe skin reactions: blistering, peeling, or widespread rash
- Signs of infection or unusual bleeding if on certain drug combinations
Topical diclofenac (gel/ointment, patch) side effects are usually local:
- Skin irritation at the application site (redness, itching, rash)
- Less commonly, systemic effects if large areas are treated or used with occlusion
Pregnancy considerations:
- Diclofenac is generally avoided during pregnancy, especially after 20 weeks, due to risks to the fetus (and potential effects on the ductus arteriosus). Talk to a clinician about safer options if you’re pregnant or planning to become pregnant.
Special cautions and interactions:
- Can increase risk of stomach ulcers/bleeding, especially with older age, prior ulcers, or with alcohol
- Kidney or liver problems can raise risk of serious side effects
- May interact with other NSAIDs, anticoagulants/antiplatelets (increases bleeding risk), certain antidepressants, blood pressure meds (diuretics, ACE inhibitors), methotrexate, and lithium
- Avoid using multiple NSAIDs together (e.g., ibuprofen with diclofenac) unless advised by a clinician
How to reduce risk:
- Use the lowest effective dose for the shortest duration
- Take with food or milk if using oral forms
- For those with GI risk, talk to a doctor about protective strategies or alternative therapies
- Follow your healthcare provider’s instructions, especially if you have kidney, liver, or heart disease
If you’d like, tell me which diclofenac form you’re asking about (oral tablet, delayed-release, topical gel, etc.) and any health conditions or other medicines you take. I can tailor the side effects and safety notes to your situation. If you notice any signs of a serious reaction, seek medical help right away.