Ibuprofen : Uses, dosing and side effects

IBUN-200 (Ibuprofen tablets USP)

Share this
Advertisement

IBUN-200 (Ibuprofen tablets USP)

Ibuprofen is effective in relieving pain and reducing the temperature in febrile patients. The drug is also a useful anti-inflammatory drug in the treatment of inflammatory disorders. Thus in the rheumatoid arthritis it relieves pain and reduces joint swelling but rarely affects the ESR or other measures of disease activity.

Ibuprofen has little effect on renal function in normal individuals but can precipitate renal failure in patients who depend upon the vasodilatory action of prostaglandin E2 or 12 to maintain renal blood flow. This occurs in hypertension, diabetes, cirrhosis of the liver and a number of other conditions. Ibuprofen may occasionally promote salt and water retention by interfering with the prostaglandin-induced inhibition of both chloride reabsorption and the action of ADH.

Pharmacokinetics

Peak serum levels are lower and later when the drug is taken after food, or when administered by suppository. Ibuprofen is rapidly eliminated from the plasma, with a half of about 2h. Except at very high concentrations, about 99% of ibuprofen is bound to a single site on plasma albumin although a second primary site can be occupied. These two primary sites have high affinities for different groups of drugs. Clinical evidence shows that ibuprofen does not affect anti-coagulation therapy with warfarin.

The high plasma protein binding of ibuprofen results in a relatively low volume of distribution, about 0.11.kg-1. Only very small amounts of ibuprofen are excreted in breast milk, not sufficient to have any effect in the infant. It is not known whether the drug crosses the placenta. Ibuprofen is extensively metabolized in the liver, with more than 90% of the dose excreted in the urine and the remainder presumably in the faeces. Less than 10% of the dose is excreted unchanged. Excretion is essentially complete within 24h.

Indications

It is used in the musculoskeletal pain, osteoarthritis, rheumatoid arthritis, juvenile chronic arthritis and acute arthritis under investigation.

Contraindications

It is contraindicated in the bronchospasm, known sensitivity to aspirin, peptic ulcer, recent gastrointestinal bleeding, renal failure and hypertension on treatment.

Adverse reactions

Potentially life-threatening effects: the major adverse reactions with ibuprofen are those affecting the gastrointestinal tract. Based on clinical trial data, serious gastrointestinal reactions, i.e. withdrawal of treatment because of haematemesis, melaena, peptic ulcer, severe gastric pain or vomiting, showed an incidence of 1.5% with ibuprofen compared with 1% for placebo and 12.5% for aspirin. Using 51 Cr-labelled red blood cells to compare ibuprofen and aspirin, there was consistently less blood loss with ibuprofen.

Severe or irreversible adverse effects: A controlled endoscopic evaluation of the effects of non-steroidal anti-inflammatory drugs on gastric mucosa confirmed that ibuprofen causes significantly fewer changes than those seen with aspirin and indomethacin. Adverse reactions affecting the liver are very rare, even in overdosage. Renal lesions are also rare, but the occasional patient may develop acute or chronic renal failure. Like other non-steroidal drugs, ibuprofen may elevate blood pressure in treated hypertensive patients.

Symptomatic adverse effects: a non-specific rash occurs occasionally, headache, depression and somnolence have been recorded, but are extremely rare. Hypersensitivity reactions can occur in patients, thus bronchospasm can be precipitated, particularly in patients with a past history of asthma, or other allergic reactions to NSAIDs.

High risk groups

Neonates: the drug should not be used in neonates

Breast milk: it does appear that on low dose ibuprofen there is a minimal excretion into the milk and therefore it is the drug of choice in it low dosage for inflammatory diseases requiring non-steroidal anti-inflammatory drugs during lactation.

Advertisement

Children: as a non-steroidal anti-inflammatory drug for use in juvenile arthritis. Dosage should be appropriate to size. 20-40mg/kg per 24 hours.

Pregnant women: low dose ibuprofen (not exceeding 600mg daily) appear to be safe for the management of rheumatoid arthritis during pregnancy.

Precautions

Tinnitus, blurred and/or diminished vision, scotomata and changes in colour vision have been reported. Medication should therefore be discontinued if any abnormal ocular manifestation develops. NSAIDs are known to produce salt and water retention.

Ibuprofen tablet should be used with caution in patients with history of hypertension or cardiac decompensation. Mild impairment of renal function can occur at high prescription dose. Because of its prolonged bleeding time effect. Ibuprofen tablet should be used with caution in patients with intrinsic coagulation defects or those receiving anti-coagulation therapy. Advanced age has only minimal influence on the pharmacokinetics of ibuprofen with no apparent need to adjust dosage in elderly patients.

Warnings

Serious gastrointestinal toxicity such as bleeding, ulceration, and perforation, can occur at any time with or without warning symptoms, in patients treated chronically with nonsteroidal anti-inflammatory drugs. Although minor upper gastrointestinal problems, such as dyspepsia, are common, usually developing early in therapy, physicians should remain alert for ulceration and bleeding in patients treated chronically with nonsteroidal anti-inflammatory drugs even in absence of previous GI tract symptoms Physicians should inform patients about the signs and symptoms of serious GI toxicity and what steps to take if they occur.

Studies to date have not identified any subset of patients not at risk of developing peptic ulceration and bleeding. Except for a prior history of serious GI events and other risk factors known to be associated with peptic ulcer disease, such as alcoholism, smoking, etc., no risk factors (e.g., age, sex) have been associated with increased risk. Elderly or debilitated patients seem to tolerate ulceration or bleeding less well than other individuals and most spontaneous reports of fatal GI events are in this population.

Studies to date are inconclusive concerning the relative risk of various nonsteroidal anti-inflammatory agents causing such reactions. High doses of any such agents probably carry a greater risk of these reactions, although controlled clinical trial showing this do not exist in most cases. In considering the use of relatively large doses (within the recommended dosage range), sufficient benefit should be anticipated to offset the potential increased risk of GI toxicity.

Dosage and administration

Adults:

Mild to moderate pain & fever: 1 tab every 4-6 hrs while symptoms persist. Total daily dose should not exceed 1200mg .

Symptoms of rheumatoid & osteoarthritis: 200-600 mg every 4-8 hrs. total daily dose should not exceed 3200mg. Frequency of reported side effects was higher at doses of 3200mg/day than at doses of </= 2400 mg/day, in clinical trials in patients with rheumatoid arthritis.

Ibuprofen tablets may be given with meals or milk to minimize the possible gastrointestinal side effects.

Children: Administration of ibuprofen tablets to children <12 years should be considered very carefully. The suggested daily dose is 20mg/kg body weight juvenile rheumatoid arthritis. For children weighing <30kg, the maximum daily dose is 500mg.

Share this

Leave a Comment

Your email address will not be published. Required fields are marked *

error: Content is protected !!
Exit mobile version