Diflunisal


Concise Prescribing Info
Indications/Uses
Listed in Dosage.
Dosage/Direction for Use
Adult : PO Mild to moderate pain Initial: 1,000 mg followed by 500 mg 8-12 hrly, depending on severity. Max: 1,500 mg/day. Osteoarthritis; Rheumatoid arthritis Initial: 500-1,000 mg/day in 2 divided doses, adjusted according to response. Max: 1,500 mg/day.
Dosage Details
Oral
Mild to moderate pain
Adult: Initially, 1,000 mg followed by 500 mg 8-12 hrly, depending on severity. Max: 1,500 mg daily. Some patients may require lower initial dose of 500 mg, followed by 250 mg 8-12 hrly.
Elderly: Initially, 500 mg followed by 250 mg 8-12 hrly. Max: 1,500 mg daily.

Oral
Osteoarthritis, Rheumatoid arthritis
Adult: 500-1,000 mg daily in 2 divided doses, adjusted according to response. Max: 1,500 mg daily.
Renal Impairment
Dose adjustment may be needed. Severe: Avoid use.
Administration
Should be taken with food.
Contraindications
Hypersensitivity to diflunisal. Patients in whom asthma, urticaria or other sensitivity reactions are precipitated by aspirin or other NSAIDS. Treatment of perioperative pain in the setting of CABG surgery; Severe renal impairment. Concomitant use w/ indometacin.
Special Precautions
Patient w/ HTN, heart failure, fluid retention, asthma, history of GI disease. Renal or hepatic impairment. Elderly. Pregnancy and lactation.
Adverse Reactions
Nausea, vomiting, dyspepsia, GI pain, bleeding or perforation; diarrhoea, constipation, flatulence, somnolence, insomnia, dizziness, tinnitus, rash, headache, fatigue, erythema multiforme, exfoliative dermatitis, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria, pruritus, sweating, dry mucous membranes, stomatitis, photosensitivity, peptic ulcer, anorexia, eructation, gastritis, liver function abnormalities, jaundice, fever, cholestasis, hepatitis, thrombocytopenia; agranulocytosis; haemolytic anaemia, nervousness, depression, hallucinations, confusion, disorientation, vertigo; light-headedness; paraesthesias, dyspnoea, palpitation, syncope, muscle cramps, nephrotic syndrome, hearing loss, chest pain.
Potentially Fatal: Serious CV thrombotic reactions, including MI and stroke; serious GI adverse events (e.g. bleeding, ulceration, and perforation of the stomach or intestines); hypersensitivity syndrome. Rarely, fulminant hepatitis, hepatic failure.
Patient Counseling Information
This drug may cause drowsiness, dizziness, blurred vision and other neurologic effects, if affected, do not drive or operate machinery.
MonitoringParameters
Evaluate cardiac risk and potential GI bleeding. Monitor CBC, chemistry profile, BP and ophth evaluation during long-term therapy.
Overdosage
Symptoms: Drowsiness, nausea, vomiting, diarrhoea, decreased urinary output, hyperventilation, tachycardia, sweating, tinnitus, disorientation, stupor, coma and cardiorespiratory arrest. Management: Supportive and symptomatic treatment. Perform gastric lavage or emesis.
Drug Interactions
Increased risk of GI bleeding w/ warfarin. Decreased absorption w/ antacids. Decreased plasma concentration w/ aspirin. Increases plasma concentration of paracetamol. Increased risk of convulsion when used w/ quinolones.
Potentially Fatal: May cause fatal GI haemorrhage w/ indometacin.
Lab Interference
May cause false increase in serum salicylate levels.
Action
Description: Diflunisal exhibits analgesic, anti-inflammatory and antipyretic activity. Though the exact mechanism have not been clearly established, the action is associated w/ the inhibition of cyclooxygenase-1 and -2 (COX-1 and -2) enzymes, resulting in decreased formation of prostaglandin precursors.
Onset: Analgesic: Approx 1 hr.
Duration: 8-12 hr.
Pharmacokinetics:
Absorption: Well absorbed from the GI tract. Time to peak plasma concentration: Approx 2-3 hr.
Distribution: Distributed into breast milk. Volume of distribution: 7.53 L. Plasma protein binding: >99%.
Metabolism: Extensively metabolised in the liver to glucuronide conjugates.
Excretion: Via urine (approx 90% as glucuronide conjugates) and faeces (<5%). Plasma half-life: Approx 8-12 hr.
Chemical Structure

Click on icon to see table/diagram/image
Storage
Store between 20-25°C.
ATC Classification
N02BA11 - diflunisal ; Belongs to the class of salicylic acids and derivatives agents. Used to relieve pain and fever.
Disclaimer: This information is independently developed by MIMS based on Diflunisal from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2020 MIMS. All rights reserved. Powered by MIMS.com
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