Select Page
A cold is an acute viral infection that affects the respiratory tract, causing inflammation of the upper respiratory tract, such as the nose, windpipe, sinuses, and larynx. It takes one to three days to incubate and disappears in four to ten days. Among the symptoms of a cold, sneezing is the first symptom to appear. Later, the sneezing is accompanied by abundant and fluid watery rhinorrhoea, nasal congestion, itchy throat, possible fever, and general malaise.

In view of the symptoms, it is easy to see that Tylenol for colds and flus is an excellent solution. Its active ingredient belongs to the group of antipyretics and analgesics, which acts by inhibiting the enzyme cyclooxygenase in the central nervous system, which produces pro-inflammatory substances, such as prostaglandins, and coagulants such as thromboxane’s.

 

What is Tylenol?

Tylenol has been succesful for those with allergies or an intolerance to asprin
It is a metabolite of phenacetin. Its analgesic and antipyretic actions are similar to the actions of acetylsalicylic acid. Although it does not have the anti-inflammatory potency of salicylates, it has been used successfully in patients with aspirin allergy or intolerance. Clinically, it has demonstrated rapid and effective antipyretic and analgesic action in infants, children, adolescents, and adults. The exact mechanism of action of Tylenol is unknown, although it is known to act centrally. Tylenol is a brand name for Acetaminophen, or Paracetamol as it is known in the UK.

 

How Does Acetaminophen Work?

 

Tylenol does not inhibit cyclooxygenases in peripheral tissues, so it lacks anti-inflammatory activity. It also appears to inhibit the synthesis and/or effects of several chemical mediators that sensitize pain receptors to mechanical or chemical stimuli. The antipyretic effects of Tylenol block endogenous pyrogen in the hypothalamic temperature-regulating center, inhibiting prostaglandin synthesis. Because of vasodilation, the heat is dissipated. Sweating and increase in blood flow have shown dissipators functions too. It does not affect prothrombin time, as it has very weak action on platelets. It does not cause gastric irritation, mucosal erosion, or bleeding that may occur after ingestion of salicylates. It does not affect the respiratory system or the cardiovascular system.

It is rapidly and completely absorbed in the digestive tract after oral ingestion. Peak plasma concentrations are reached after 30-60 min but are not fully associated with maximal analgesic effects. Plasma protein binding is 25 %. Approximately one-quarter of the dose undergoes first-pass metabolism in the liver. Most of the therapeutic dose is also metabolized in the liver, producing glucuronide conjugates and sulfates, which are subsequently excreted in the urine. Between 10 and 15 % of the dose undergoes oxidative metabolism by cytochrome P450 isoenzymes, later conjugated to cysteine and mercapturic acid. After an overdose, if there is malnutrition or alcoholism, hepatic depletion of glucuronides and sulfates occurs, so Tylenol undergoes oxidative metabolism, which is the most toxic, via the CYP2E1 and CYP1A2 enzyme system. This metabolite can also be produced when Tylenol is administered with drugs that are hepatic inducers. In renal failure, the metabolites may accumulate, but not the unchanged drug. The elimination half-life of Tylenol is 2-4 h in patients with normal hepatic function and is virtually undetectable in plasma 8 h after administration. In patients with hepatic dysfunction, the half-life is substantially increased, which may lead to the development of hepatic necrosis.

 

How Does Acetaminophen Work?

 

Tylenol does not inhibit cyclooxygenases in peripheral tissues, so it lacks anti-inflammatory activity. It also appears to inhibit the synthesis and/or effects of several chemical mediators that sensitize pain receptors to mechanical or chemical stimuli. The antipyretic effects of Tylenol block endogenous pyrogen in the hypothalamic temperature-regulating center, inhibiting prostaglandin synthesis. Because of vasodilation, the heat is dissipated. Sweating and increase in blood flow have shown dissipators functions too. It does not affect prothrombin time, as it has very weak action on platelets. It does not cause gastric irritation, mucosal erosion, or bleeding that may occur after ingestion of salicylates. It does not affect the respiratory system or the cardiovascular system.

It is rapidly and completely absorbed in the digestive tract after oral ingestion. Peak plasma concentrations are reached after 30-60 min but are not fully associated with maximal analgesic effects. Plasma protein binding is 25 %. Approximately one-quarter of the dose undergoes first-pass metabolism in the liver. Most of the therapeutic dose is also metabolized in the liver, producing glucuronide conjugates and sulfates, which are subsequently excreted in the urine. Between 10 and 15 % of the dose undergoes oxidative metabolism by cytochrome P450 isoenzymes, later conjugated to cysteine and mercapturic acid. After an overdose, if there is malnutrition or alcoholism, hepatic depletion of glucuronides and sulfates occurs, so Tylenol undergoes oxidative metabolism, which is the most toxic, via the CYP2E1 and CYP1A2 enzyme system. This metabolite can also be produced when Tylenol is administered with drugs that are hepatic inducers. In renal failure, the metabolites may accumulate, but not the unchanged drug. The elimination half-life of Tylenol is 2-4 h in patients with normal hepatic function and is virtually undetectable in plasma 8 h after administration. In patients with hepatic dysfunction, the half-life is substantially increased, which may lead to the development of hepatic necrosis.

Precautions For Use

Empty pill sachets with pills surrounding and 'short term use' writing

Because of its antipyretic and analgesic action, Tylenol is indicated for the treatment of illnesses involving fever and, or mild to moderate pain in adults and children. In the latter, it is considered the antipyretic and analgesic of choice. It will therefore be useful for treating headaches, dental pain, menstrual pain, non-inflammatory injuries, or the treatment of flu symptoms.

Tylenol should be administered with caution, avoiding prolonged treatment in patients with anemia, heart or lung disease, or renal dysfunction (in the latter case, occasional use is acceptable, but prolonged administration of high doses may increase the risk of adverse renal effects).

The use of Tylenol in patients who regularly consume alcohol must be with caution. Ingestion of 3 or more alcoholic drinks for prolonged periods may increase the risk of liver damage or gastrointestinal tract bleeding associated with the use of Tylenol, so these conditions should be considered when prescribing the drug. In chronic alcoholics, no more than 2g/day of Tylenol should be administered.

Caution is advised in asthmatic patients sensitive to acetylsalicylic acid because slight bronchospastic reactions with Tylenol (cross-reaction) have been described in these patients. However, only in a minority of such patients may it cause serious reactions in some cases, especially when administered in high doses.

 If the pain lasts for more than five or more days or fever for more than three days, or if other symptoms worsen or appear, the clinical situation should be re-evaluated. When doses of less than 500 mg of Tylenol per dose are required, other presentations of Tylenol should be used to suit the required dosage.

It is also contraindicated for people with hypersensitivity; it is metabolized in the liver and should be administered with caution in patients with liver damage, as well as in those who are receiving hepatotoxic drugs or who have nephropathy. Tylenol should also not be given for prolonged periods or to pregnant women.

 

Conclusion 

Tylenol is a medicine used primarily to relieve fever and mild to moderate pain. It is said to have analgesic and antipyretic properties. However, it should be used in moderation, as excessive use can cause liver problems.