Paracetamol

    We commonly use paracetamol in our daily life. What is paracetamol? Paracetamol is also known as acetaminophen. Paracetamol is belongs to a group of pain-killers or aniline analgesics. Paracetamol is an organic compound that consists of a benzene ring core that substituted with one hydroxyl group and the nitrogen atom of an amide group in the 1,4 para pattern. The amide group in the paracetamol is the acetamide.

Administration of paracetamol

    There are few ways of administration of paracetamol into the body such as the oral route, intravenous, rectal route and enteral route. Oral route is the process by delivering the paracetamol by the mouth through the alimentary tract. Oral route can be divided into two types which are oral suspension and the oral tablets. Intravenous is placing an appropriate dose in the syringe and directly injected into the vein. Rectal route is  by removing the foil wrapper of paracetamol and insert well up into the rectum. The absorption of the rectum is better compared to the others because the rectum is full of blood capillaries. Enteral route is crushing the oral tablets and mixing with water prior to enteral feeding tube administration may be suitable alternative to liquid formulations of acetaminophen. Below are the pictures for oral suspension and oral tablets of paracetamol:
   

The uses of paracetamol

    Paracetamol is used mostly for pain reliever and fever reducer. Besides that, there are many uses for paracetamol too such as to treat headache, muscle aches, arthritis, backache, toothaches and colds. However, paracetamol does not have any effect on the inflammation and swelling of the joint. Paracetamol can also be used in more severe pain such as a post-surgical pain and palliative care is provided for advanced cancer patients.

Paracetamol should not be used overdose. The first symptoms of using overdose paracetamol are:

1. Loss of appetite.
2. Nausea.
3. Vomiting.
4. Stomach pain.
5. Sweating.

If did not applied an urgent medication, the symptoms later on are:

1. Feel pain in the upper stomach.
2. Thick concentration of urine.
3. Yellowing on the skin.

There are few medicines should be avoided after eaten the paracetamol such as:

1. Barbiturates, also known as sleeping pills.
2. Tricyclic antidepressants.
3. Colestyramine, used to treat high cholesterol.
4. Warfain, used to thin the blood and prvent blood clotting.
5. Zidovudine, used in the treatment of HIV infections and AIDS.
6. Domperidone and metoclopramide, used to cure nausea and vomiting.
7. Anticonvulsants, used in the treatment of epilepsy.
8. Oral contraceptives pills.

    Paracetamol is harmful to animals especially to cats, dogs or even snake. Paracetamol will breaks down the necessary glucuronyl transferase enzymes. As for dogs, paracetamol is used for the treatment of musculosketetal pain. The toxicity of paracetamol can caused the dogs to have liver damage.

Side effects of using paracetamol

    Paracetamol is a harmful medicine if overdose. There are few side effects of using paracetamol. One of the side effects is will cause liver and kidney damage when is overdose. Toxicity of paracetamol arises due to the  quinone metabolite. As the toxicity of paracetamol increases without control may cause death within few days. Another side effect is will cause hypotension if paracetamol is given through blood infusion in a high dose that recommended. To avoid the absorption of paracetamol after an overdose condition, activated charcoal will be used so that the can lower down the absorption of the paracetamol.

Brands for paracetamol

    There are many brands name of paracetamol in different countries. In Malaysia, paracetamol is known as Panadol. Another brand name of paracetamol in Malysia is Uphamol. Panadol is also a brand name of paracetamol in many countries not only in Malaysia such as United States, Australia, Hong Kong, Indonesia, Taiwan. Turkey, Ireland, Sri Lanka, Switzerland and many more. Our neighbour, Thailand has a different brand name for paracetamol which is called as Sara. There are many other brands name in other countries such as Zolben, Tapsin, Scanol, Revanin, Reliv, Plicet and Etpara.

Precaution of paracetamol

    Paracetamol should be stored carefully because paracetamol is harmful and cannot be taken frequently. Besides that, paracetamol should be prevented from the light and always alert with the expiry dare so that eating expired paracetamol could be avoided. Paracetamol should be kept out of the reach of the children and stored in a original package in a temperature below 25°C.

 This is the skeleton structure of the paracetamol.

Metabolism of paracetamol 

    Paracetamol is metabolisms in the liver first and then transforms into toxic or non toxic products. There are three metabolism pathways. The first pathway is glucuronidation reaction. This reaction can accounts around 40% to two-thirds of the metabolism of paracetamol. The second pathway is the sulfation which can account around 20% to 40% of the metabolism. The last pathway is the n-hydoxylation and rearrangement and then proceeds to GSH conjugation reaction. This reaction accounts less than 15% of the metabolism of paracetamol. The products from all the three pathways that are inactive and non-toxic will be excreted from the kidneys. In the n-hdroxylation and rearrangement reaction and continues with GSH conjugation reaction will produce an intermediate product which is known as NAPQI. This intermediate product is very toxic and responsible for the toxic effects of paracetamol. In usual doses, NAPQI can be detoxified by conjugation with glutathione. However, in overdoses, NAPQI becomes saturated and accumulated and this can cause liver and renal toxicity.

     

Preparation of paracetamol

    Paracetamol can be prepared in laboratory by using nitrating phenol with sodium nitrate. The reaction occurs when para-nitrophenol is separates from the ortho-byproduct and reduces to the nitro group with sodium borohydride. The product is 4-aminophenol. Phenol is a strongly activating reagent, therefore the reaction only requires mild conditions.

Issue related to paracetamol

    There have been an issue saying that paracetamol found to be linked to blood cancers. This article was written on the 11 May 2011 by Daily Mail Reporter. It was said that regular users of paracetamol increased the risk of developing blood cancers such as lymphoma, myelodysplastic syndrome or MDS, found by the researchers. Paracetamol that contained acetaminophen has been linked to cases of blood cancers in a number of individuals who were frequently took the paracetamol. In the earlier work, acetaminophen is also linked to asthma and eczema, but scientist did not confirm whether acetaminophen is the actual culprit or the innocent bystander. There has been a research in Washington State about the often use of paracetamol. The scientists followed around 65,000 older women and men for the research of the participants about their use in of paracetamol over the past ten years and made sure that no one had cancer except for skin cancer. According to Emily White of the Fred Hutchinson Cancer Research Centre in Seattle, who worked on the new research said that a person who is age 50 and above has about one percent risk in ten years of getting one the blood cancers. Their studied suggested that if acetaminophen are used four times a week for at least four years, as a result the risk of getting blood cancer will be increased to about two percent. Over some six years on average, less than one percent from 65,000 older women and men or about 577 people were developed a blood cancer. More than nine percent of people who developed one of the blood cancers frequently used acetaminophen compared to five percent of people who did not sick. A cancer prevention expert at the University of Texas MD Anderson Cancer Centre in Houston, Dr. Raymond DuBois said that acetaminophen worked very differently than other painkillers and assumed that might have a different effect on cancers. However, Emily White said it is too soon to make any recommendations based ob the new study and none of the painkillers are free of side effects. Long-term use of any drugs might have adverse effects too.

A Good Helper of Our Life ------ Detergent

  In everywhere no matter is supermarket, grocery store or even a house, you can always see the appearance of detergent. It's not an expensive thing but it is necessary for everyone in everyday life for daily use. However, is that anyone really know what is meant by detergent and how is it form in our life?

  In fact, a detergent is a sodium or potassium salt of alkyl sulphonic acid or alkylbenzene sulphonic acid. According to the Oxford Dictionary, a detergent is a water-soluble cleansing agent which combines with impurities and dirt to make them more soluble, and differs from soap in not forming a scum with the salts in hard water.
   
    Besides, detergents are usually made from synthetic resources such as petroleum fractions. They were developed during the Second World War in response to a shortage of animal fats and vegetable oils. The general formulae for two common detegents are shown below where R represents a long-chain hydrocarbon.

   A long-chain hydrocarbon obtained from petroleum fractions is converted into an organic acid through a series of steps during the preparation of detergents. The organic acid is then neutralised with sodium hydroxide solution to produce a neutral salt which is a detergent.

Preparation of sodium alkyl sulphate

Step 1: Reaction with concentrated sulphuric acid

         

A long-chain alcohol reacts with concentrated sulphuric acid to form alkyl hydrogen sulphate.

                                                                                                                                  

Step 2: Neutralisation with sodium hydroxide solution

The resulting acid is then converted to the sodium salt by a reaction with sodium hydroxide.

Cleaning action of detergent

       

    We all know that detergents are used to clean items by removing bacteria and dirt. However, not many people understand how exactly these cleaners work. Detergents work because they contain surfactants. A surfactant is any molecule that reduces water tension and bonds to dirt. Once the dirt and surfactants are bonded, the rinse water washes the surfactants away, taking dirt and grime with it. Synthetic surfactants bond to particles because they hold a charge. Depending on the surfactant used, when mixed with water it can take on a positive or negative charge. Most surfactants used in detergents become positively charged when mixed with water.

     Basically, detergents are more complex and able to clean better in hard water than soap because they do not produce soap scum. Detergents are usually synthetic compounds that originate from crude oil. To isolate and extract DNA, scientists treat plant or animal samples with a detergent. This breaks down cell membranes, allowing scientists to study the DNA.

    
      Detergents are used for cleaning because pure water can't remove oily, organic soiling. Surfactants lower the surface tension of water, essentially making it 'wetter' so that it is less likely to stick to itself and more likely to interact with oil and grease.

     
      Like soaps, detergents have hydrophobic or water-hating molecular chains and hydrophilic or water-loving components. The hydrophobic hydrocarbons are repelled by water, but are attracted to oil and grease. The hydrophilic end of the same molecule means that one end of the molecule will be attracted to water, while the other side is binding to oil.
    
      Swishing the soapy water around allows the detergent to pull the grime away from clothes or dishes and into the larger pool of rinse water. Rinsing washes the detergent and soil away. Warm or hot water melts fats and oils so that it is easier for the detergent to dissolve the soil and pull it away into the rinse water. Detergents are similar to soap, but they are less likely to form films (soap scum) and are not as affected by the presence of minerals in water (hard water).

   Detergents are cleansing agents that are effective in soft water as well as hardwater. This is because detergents do not form scum with Mg+ and Ca2+ ions foundin hard water. The detergents ions (R –O – SO3- and R – SO3- ) react with Mg+ and Ca2+ ions in hard water.
    
   However, the magnesium salts and calcium salts which are formed are soluble in water. Hence, the scum is not formed and the detergents are still activein hard water and lathers easily.Detergents are synthetic cleansing agents. This means that the structure of the hydrocarbon chain can be modified to produce detergents with specific properties.
  
    Nowadays, different types of detergents have been synthesised for specific uses such as shampoos and dish cleaner.Furthermore, detergents are also effective in acidic water because H+ ion is acidic water do not combined with detergents ions.

    Nowadays, the modern detergent in the market that used for washing clothes contain a few sorts of additives to increase their cleaning power and make them to attractive and saleable. 

a) Whitening agents
   Example: Sodium perborate.
   Function: Through the oxidation process to convert stains into colourless substances.

(b) Biological enzymes
   Examples: Amylases, proteases, cellulases and lipases.

   Function: To remove protein stains such as blood, milk and tomato sauce which are insoluble                               stains in water.

(c) Fillers and drying agents

   Examples: Sodium sulphate and sodium silicate.

   Function: To ensure that the detergent is always in a dry condition, to add to the bulk of the detergent and enable it to be poured easily.

(d) Fragrances
   Function: To make clothes fresh and clean and to add fragrance to both the detergent and fabrics.

(e) Builder
    Example: Sodium tripolyphosphate
    Function: To soften the hard water and increases the pH value of water so that muddy dirt can be removed.

(f) Suspension agents
    Example: Carboxymethylcellulose (CMC)
    Function: To prevent the dirt particles redepositing onto cleaned fabrics.

  

     In the nutshell, there are too many types of detergents in the world and we could not without detergents in our life because detergent is really a good helper in our life in anytime and any place to help us to solve many problems. Cherish what you have in your life and use it properly!