General

diclofenac potassium

• Cataflam

• Apo–Diclo Rapide [Canada]

diclofenac sodium

• Apo-Diclo [Canada]

• Voltaren

diclofenac topical

• Solaraze

Pregnancy Category
Category B (topical)
Category C (oral)

Ther. class.
nonopioid analgesics
nonsteroidal anti inflammatory agents

Indications

• PO: Management of inflammatory disorders including

» Rheumatoid arthritis

» Osteoarthritis

» Ankylosing spondylitis

• Primary dysmenorrhea

• Relief of mild to moderate pain

• Topical: Treatment of actinic keratoses

Action

Inhibits prostaglandin synthesis

Therapeutic Effect(s):

• Suppression of pain and inflammation

• Topical: Clearance of actinic keratosis lesions

Pharmacokinetics

Absorption: Undergoes first-pass metabolism by liver which results in 50% bioavailability Oral diclofenac sodium is a delayed-release dosage form. Diclofenac potassium is an immediate-release dosage form. 10% of topically applied diclofenac is systemically absorbed

Distribution: Crosses the placenta

Protein Binding: >99%

Metabolism and Excretion: Metabolized by the liver to several metabolites; 65% excreted in urine, 35% in bile

Half-life: 2 hr

TIME/ACTION PROFILE

ROUTE	ONSET	PEAK	DURATION
PO (inflammation)	few days–1 wk	2 wk or more	unknown
PO (pain)	30 min	unknown	up to 8 hr
Topical	unknown	30 days*	unknown

*Complete healing of lesions following cessation of therapy

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity to diclofenac or other components of formulation

• Cross-sensitivity may occur with other NSAIDs including aspirin

• Active GI bleeding/ulcer disease

• Patients undergoing coronary artery bypass graft surgery

Use Cautiously in:

• Severe renal/hepatic disease

• Cardiovascular disease or risk factors for cardiovascular disease (may risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, especially with prolonged use)

• History of porphyria

• History of peptic ulcer disease and/or GI bleeding

• Geri: Geriatric patients (dosage reduction recommended; more susceptible to adverse reactions, including GI bleeding)

• Bleeding tendency or concurrent anticoagulant therapy

• OB: /Lactation: Pregnancy and lactation (not recommended for use during second half of pregnancy)

• Pedi: Pregnancy, lactation, and children (safety not established)

Adverse Reactions/Side Effects

For oral diclofenac unless noted

CNS: dizziness, headache.

CV: hypertension.

EENT: tinnitus.

GI: GI BLEEDING, abdominal pain, constipation, diarrhea, dyspepsia, flatulence, heartburn, liver enzyme elevation, nausea, vomiting.

GU: acute renal failure, hematuria.

Derm: EXFOLIATIVE DERMATITIS, STEVENS-JOHNSON SYNDROME, TOXIC EPIDERMAL NECROLYSIS, pruritis, rashes, eczema, photosensitivity.

F and E: edema.

Hemat: anemia, prolonged bleeding time.

Local: Topical only—contact dermatitis, dry skin, exfoliation.

Misc: ALLERGIC REACTIONS INCLUDING ANAPHYLAXIS.

*CAPITALS indicates life-threatening.
*italic indicates most frequent.

Interactions

Primarily noted for oral administration

Drug-Drug

• adverse GI effects with aspirin, other NSAIDs, or corticosteroids

• May effectiveness of diuretics, or antihypertensives

• May levels/risk of toxicity from cyclosporine, lithium, or methotrexate

• risk of bleeding with some cephalosporins, thrombolytic agents, antiplatelet agents, or warfarin

• Concurrent use of oral NSAIDs during topical diclofenac therapy should be minimized

Drug-Natural Products
bleeding risk with arnica, chamomile, clove, dong quai, feverfew, garlic, ginger, ginkgo, Panax ginseng, and others

Route/Dosage

• Different formulations of oral diclofenac (diclofenac sodium enteric-coated tablets, diclofenac sodium extended-release tablets, and diclofenac potassium immediate-release tablets are not bioequivalent and should not be substituted on a mg-to-mg basis.

Diclofenac Potassium

• PO (Adults):
Analgesic/antidysmenorrheal—100 mg initially, then 50 mg 3 times daily as needed;
Rheumatoid arthritis—50 mg 3–4 times daily, after initial response reduce to lowest dose that controls symptoms;
Osteoarthritis—50 mg 2–3 times daily, after initial response reduce to lowest dose that controls symptoms.

Diclofenac Sodium

• PO (Adults):
Rheumatoid arthritis (delayed-release [enteric-coated] tablets)—50 mg 3–4 times daily
or 75 mg twice daily; after initial resopnse reduce to lowest dose that controls symptoms (usual maintenance dose 25 mg 3 times daily).
Rheumatoid arthritis (extended-release tablets)—100 mg once daily, if unsatisfactory response, dose may be to 100 mg twice daily.
Osteoarthritis (delayed-release [enteric-coated] tablets)—50 mg 2–3 times daily
or 75 mg twice daily; after initial response, to lowest dose that controls symptoms.
Osteoarthritis (extended-release tablets)—100 mg once daily.
Ankylosing spondylitis (delayed-release [enteric-coated] tablets)- 25 mg 4 times daily, with an additional 25 mg given at bedtime, if necessary.

• Topical (Adults): Apply to lesions twice daily for 60–90 days.

Availability

• Diclofenac potassium immediate-release tablets: 50 mg

» Cost:
Generic: $59.98/100.

• Diclofenac sodium delayed-release (enteric-coated) tablets: 25 mg, 50 mg, 75 mg

» Cost:
Generic: 25 mg $42.80/100, 50 mg $37.08/100, 75 mg $44.98/100.

• Diclofenac sodium extended-release tablets: 75 mg[canada], 100 mg

» Cost:
Generic: 100 mg $208.78/90.

• Gel: 3% in 50- and 100-g tubes

» Cost: $193.36/50 g, $275.68/100 g.

• In combination with: 200 mcg misoprostol (Arthrotec). See combination drugs

Assessment

• Patients who have asthma, aspirin-induced allergy, and nasal polyps are at risk for developing hypersensitivity reactions

Pain

• Assess pain and limitation of movement; note type, location, and intensity before and 30–60 min after administration

Arthritis

• Assess arthritic pain (note type, location, intensity) and limitation of movement before and periodically during therapy

Actinic Keratosis

• Assess lesions prior to and periodically during therapy

Lab Test Considerations

• Diclofenac has minimal effect on bleeding time and platelet aggregation

» May cause in hemoglobin and hematocrit

» Monitor liver function tests within 8 wk of initiating diclofenac therapy and periodically during therapy. May cause serum alkaline phosphatase, LDH, AST, and ALT concentrations

» Monitor BUN and serum creatinine periodically during therapy. May cause BUN and serum creatinine

Potential Nursing Diagnoses

• Acute pain (Indications)

• Impaired physical mobility (Indications)

Implementation

• Do not confuse Cataflam (diclofenac) with Catapres (clonidine)

» Administration in higher than recommended doses does not provide increased effectiveness but may cause increased side effects. Use lowest effective dose for shortest period of time

• PO: Take with food or milk to minimize gastric irritation May take first 1–2 doses on an empty stomach for more rapid onset. Do not crush or chew enteric-coated or extended-release tablets

• Dysmenorrhea: Administer as soon as possible after the onset of menses. Prophylactic treatment has not been shown to be effective

• Topical: Gel should be applied to intact skin; do not use on open wounds. An adequate amount of gel should be applied to cover the entire lesion

Patient/Family Teaching

• PO: Instruct patient to take diclofenac with a full glass of water and to remain in an upright position for 15–30 min after administration. Take missed doses as soon as possible within 1–2 hr if taking once or twice a day or unless almost time for next dose if taking more than twice a day. Do not double doses

» Caution patient to avoid concurrent use of alcohol, aspirin, acetaminophen, other NSAIDs, or other OTC medications without consulting health care professional

» May cause drowsiness or dizziness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known

» Instruct patient to notify health care professional of medication regimen before treatment or surgery

» Caution patient to wear sunscreen and protective clothing to prevent photosensitivity reactions

» Instruct female patients to inform health care professional if they plan or suspect pregnancy

» Advise patient to consult health care professional if rash, itching, visual disturbances, tinnitus, weight gain, edema, black stools, persistent headache, or influenza-like syndrome (chills, fever, muscle aches, pain) occurs

• Topical: Advise patient to minimize use of concurrent NSAIDs during topical therapy

» Instruct patient to avoid covering lesion with occlusive dressing and to avoid applying sunscreen or cosmetics to the affected area

» Advise patient that it may take up to 1 mo for complete healing of the lesion to occur

Evaluation/Desired Outcomes

• Decrease in severity of mild-to-moderate pain

» Increased ease of joint movement. Patients who do not respond to one NSAID may respond to another. May require 2 wk or more for maximum effects

• Decrease in or healing of lesions in actinic keratosis. Optimal effect may not be seen until 30 days after discontinuation of therapy. Lesions that do not heal should be re-evaluated

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