Diclofenac

VOLTAREN

What it isCOX-1 and COX-2 inhibitor with relative COX-2 preference; oral or topical treatment of arthritis and acute pain.

Why this oneIts topical formulation treats localized osteoarthritis with much less systemic exposure than oral diclofenac.

What limits itIts cardiovascular and hepatic risks are unusually prominent among traditional NSAIDs; it can also raise lithium exposure.

FDA-approved for

BOXED WARNING Risk of serious cardiovascular thrombotic events and GI bleeding/ulceration/perforation.

FDA dosing	Population	Start	Max
Osteoarthritis	Adults	50 mg BID–TID or 75 mg BID (100–150 mg/day)	150 mg/day
Rheumatoid arthritis	Adults	50 mg TID–QID or 75 mg BID (150–200 mg/day)	200 mg/day
Ankylosing spondylitis	Adults	25 mg QID plus 25 mg QHS if needed (100–125 mg/day)	125 mg/day

Renal Undefined

Hepatic Undefined

Use the lowest effective dose for the shortest duration consistent with treatment goals
Different diclofenac formulations are not necessarily bioequivalent even at the same mg strength

History of asthma, urticaria, or allergic-type reactions after aspirin or other NSAIDs
In the setting of coronary artery bypass graft (CABG) surgery

Pregnancy Undefined

Lactation Undefined

⚠ BOXED WARNINGS

Cost, est. cash$300–$2,500/month

Generic entry2030 est.

Therapeutic safety burden2 / 4

Overdose danger3 / 4

Weight-gain liability0 / 4

Sedation liability0 / 4

QT / Torsades0 / 4

Direct muscarinic antagonism0 / 4

Embryofetal risk3 / 4

Legacy pregnancy categoryMultiple / indication-, trimester- or formulation-dependent

Defining liabilityGI bleeding, kidney injury, hypertension and fluid retention; many agents increase lithium concentrations.

Box: minimal PK interactions