Diflunisal

Diflunisal

File:Diflunisal-2D-skeletal.png
Clinical data
Pregnancy category	AU: C US: C (Risk not ruled out)
Routes of administration	Oral
ATC code	N02BA11 (WHO)
Legal status
Legal status	UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	80-90%
Protein binding	>99%
Metabolism	Hepatic
Elimination half-life	8 to 12 hours
Excretion	Renal
Identifiers
IUPAC name 5-(2,4-difluorophenyl)-2-hydroxy-benzoic acid
CAS Number	22494-42-4
PubChem CID	3059
DrugBank	APRD00922
E number	{{#property:P628}}
ECHA InfoCard	{{#property:P2566}}
Chemical and physical data
Formula	C13H8F2O3
Molar mass	250.198 g/mol

Diflunisal is a generic NSAID (non-steroidal anti-inflammatory drug). It is often used under the brand name Dolobid marketed by Merck & Co. Diflunisal acts by inhibiting the production of prostaglandin, a hormone that creates inflammation and stimulates the neuro receptors for pain. Though diflunisal has an onset of 1 hour, and maximum analgesia at 2 to 3 hours, the diflunisal plasma levels will not be steady until repeated doesages are achieved. To increase the rate at which the diflunisal plasma levels become steady, a loading dose is usually used. It is primarily used to treat symptoms of arthritis.

Overdose

Deaths that have occurred from diflunisal usually involved mixed drugs and or extremely high dosages. The oral LD₅₀ is 500 mg/kg. Symptoms of overdose include, coma, tachycardia, stupor, and vomiting. The lowest dose without the presence of other medicines which caused death was 15 grams. Mixed with other medicines, a death at 7.5 grams has also occurred. Diflunisal usually comes in 250 or 500 mg, thus it is relatively hard to overdose by accident.

Abuse

This medication has no side effects like those of recreational drugs.

Indicated for: Pain, mild-moderate Osteoarthritis Rheumatoid arthritis Injury to tendons Inflammation Do not cut/crush/chew. Monitor blood pressure. Use lowest effective dose for shortest duration.

Side effects: Cardiovascular: Irregular heart beat (!) This medication may increase risk of serious and potentially fatal cardiovascular thrombotic events, MI, and stroke (!) Risk may increase with duration of use (!) Increased risk for Cardiovascular disease history (!) Contraindicated for Heart Bypass peri-op pain (!) Ear, nose, and throat: Ringing in the ears (!) Eye: Yellowing of eyes (!) Gastrointestinal: Increased risk of serious GI adverse events including bleeding, ulceration, and stomach or intestine perforation which can be fatal: may occur at any time during use and without warning. Elderly at greater risk for serious GI events (!) Abdominal pain and cramps Constipation Gas & Flatulence Diarrhea Nausea & Vomiting Dyspepsia Central Nervous System: Drowsiness Dizziness Headache Insomnia Fatigue Somnolence Psychiatric: Nervousness Skin: Swelling of the feet, ankles, lower legs, and hands (!) Yellowing of skin (!) Rash Ecchymosis Contraindications: Hypersensitivity to aspirin/NSAID-induced asthma or urticaria Aspirin triad Pregnancy 3rd trimester CABG surgery (peri-op pain) Cautions: Cardiovascular disease Cardiac risk factors Hypertension Congestive Heart Failure Elderly or debilitated Impaired liver function Impaired kidney function Dehydration Fluid retention GI bleed history/PUD Asthma Coagulopathy Smoker Corticosteriod use Anticoagulant use Alcohol use Diuretic use ACE Inhibitor use Prolonged use Precautions: If symptoms labeled, (!), appear, stop usage immediately and contact your doctor. Overdose is possible and deaths have occurred. Do not take while on other pain medications. Do not take while pregnant or breast feeding.

External links

• http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a684037.html
• http://www.medsafe.govt.nz/Profs/Datasheet/discontinued/ansaltab.htm
• Dolobid Prescribing Information (manufacturer's website)
• Dolobid Medication Guide (manufacturer's website)
• Diflunisal (patient information)