Panadol

What is panadol?

I don't think someone has to tell what panadol is for any Maldivian. For years we have been using this "for our enjoyment" and to cure all the disease. I had a friend who cannot fall sleep without having two panadol capsules. By the way as I have decided write about panadol, must tell what is panadol.

Panadol is the GlaxoSmithKline brand name of the phamaceutical paracetamol (para-acetylaminophenol), which is administered to reduce pain and fever. There are many similar products marketed under other names. For example, in India, paracetamol is sold as Crocin and in Colombia it is marketed as Dolex. It is sold in more than 85 countries. However, in North America, Johnson and Johnson's Tylenol is the leading brand of paracetamol.

Panadol is sold in three varieties in many markets:

1. plain
2. rapid
3. extra, which includes caffeine. This version is marketed as Tylenol Ultra, and contains 500 mg of paracetamol (acetaminophen) and 65 mg of caffeine.

Side Effects

General
In general, acetaminophen is well-tolerated when administered in therapeutic doses.

Hepatic

Hepatic side effects including severe and sometimes fatal dose dependent hepatitis have been reported in alcoholic patients. Hepatotoxicity has been increased during fasting. Several cases of hepatotoxicity from chronic acetaminophen therapy at therapeutic doses have also been reported despite a lack of risk factors for toxicity.

Alcoholic patients may develop hepatotoxicity after even modest doses of acetaminophen. In healthy patients, approximately 15 grams of acetaminophen is necessary to deplete liver glutathione stores by 70% in a 70 kg person. However, hepatotoxicity has been reported following smaller doses. Glutathione concentrations may be repleted by the antidote N-acetylcysteine. One case report has suggested that hypothermia may also be beneficial in decreasing liver damage during overdose.

In a recent retrospective study of 306 patients admitted for acetaminophen overdose, 6.9% had severe liver injury but all recovered. None of the 306 patients died.

A 19-year-old female developed hepatotoxicity, reactive plasmacytosis and agranulocytosis followed by a leukemoid reaction after acute acetaminophen toxicity.

Gastrointestinal

One study has suggested that acetaminophen may precipitate acute biliary pain and cholestasis. The mechanism of this effect may be related to inhibition of prostaglandin and alterations in the regulation of the sphincter of Oddi.

Gastrointestinal side effects are rare except in alcoholics and after overdose. Cases of acute pancreatitis have been reported rarely.

Renal

Renal side effects are rare and have included acute renal failure, acute tubular necrosis, and interstitial nephritis. Adverse renal effects are most often observed after overdose, after chronic abuse (often with multiple analgesics), or in association with acetaminophen-related hepatotoxicity.

Acute tubular necrosis usually occurs in conjunction with liver failure, but has been observed as an isolated finding in rare cases. A possible increase in the risk of renal cell carcinoma has been associated with chronic acetaminophen use as well.

One case-control study of patients with end-stage renal disease suggested that long term consumption of acetaminophen may significantly increase the risk of end-stage renal disease particularly in patients taking more than two pills per day.

However, a recent cohort study of analgesia use of initially healthy men concluded that moderate use of analgesics including acetaminophen was not associated with increased risk of renal disease.

Hypersensitivity

Hypersensitivity side effects including anaphylaxis and fixed drug eruptions have been reported rarely in association with acetaminophen use.

Hematologic

Hematologic side effects including rare cases of thrombocytopenia associated with acetaminophen have been reported. Acute thrombocytopenia has also been reported as having been caused by sensitivity to acetaminophen glucuronide, the major metabolite of acetaminophen. Methemoglobinemia with resulting cyanosis has been observed in the setting of acute overdose.

Dermatologic

Dermatologic side effects including erythematous skin rashes associated with acetaminophen have been reported, but are rare. Acetaminophen associated bullous erythema and purpura fulminans have been reported. One case of toxic epidermal necrolysis associated with acetaminophen administered to a pediatric patient has been reported.

Respiratory

Respiratory side effects including a case of acetaminophen-induced eosinophilic pneumonia have been reported.

Cardiovascular

Cardiovascular side effects including two cases of hypotension have been reported following the administration of acetaminophen.

Two cases hypotension have been reported following the administration of acetaminophen. Both patients experienced significant decreases in blood pressure. One of the two patients required pressor agents to maintain adequate mean arterial pressures. Neither episode was associated with symptoms of anaphylaxis. Neither patient was rechallenged after resolution of the initial episode.

Metabolic

Metabolic side effects including metabolic acidosis have been reported following a massive overdose of acetaminophen.

In the case of metabolic acidosis, causality is uncertain as more than one drug was ingested. The case of metabolic acidosis followed the ingestion of 75 grams of acetaminophen, 1.95 grams of aspirin, and a small amount of a liquid household cleaner. The patient also had a history of seizures which the authors reported may have contributed to an increased lactate level indicative of metabolic acidosis.