Diclofenac

What it is

Diclofenac is a non-steroidal anti-inflammatory drug; its oral and injectable forms are prescription only. It inhibits the cyclo-oxygenase enzymes, cutting production of the prostaglandins that keep pain and swelling going. It is used for pain and inflammation.

Used for

• Pain
• Inflammation

What to know while taking it

It is taken with food, because the prostaglandins it suppresses also protect the stomach lining, and that is the reason for the bleeding warning. Diclofenac is watched more closely than most of its class for effects on the liver, so ALT and AST belong on the list alongside creatinine and eGFR for the kidney. It can move blood pressure and weaken lisinopril, losartan and furosemide, and taking it with prednisolone stacks two things that irritate the stomach lining. It is not taken with warfarin, and doubling up with ibuprofen or naproxen adds bleeding risk without adding pain relief.

When to see a doctor

Black or tarry stools, vomiting that looks like coffee grounds, or upper-abdominal pain that keeps returning point to bleeding and need a doctor promptly. Yellow eyes or skin, dark urine or lasting nausea point to the liver, and swollen ankles or falling urine output to the kidney; both mean see a doctor.

Worth knowing

• Raises the risk of stomach bleeding
• Watch liver enzymes
• Caution with kidney disease
• Can lower blood pressure

Markers to watch

• ALT
• AST
• Creatinine
• eGFR