OPTION D: MEDICINES AND DRUGS SYLLABUS REFERENCE D3 ANALGESICS

D.3.1 Describe and explain the different ways that analgesics prevent pain. Objectives: 3 D.3

ANALGESICS is derived from the word ANALGESIA, which means a sense of well being. Analgesics are basically pain and fever relievers. D.3

Analgesics can be of two types, D.3.1 Analgesics can be of two types, The Strong Analgesics (Commonly known as narcotics) The Mild Analgesics (Non-narcotics) Both analgesics work in similar ways- They prevent the brain from detecting pain and other such unpleasant stimuli. However, the manner in which this is done varies. D.3

MILD ANALGESICS REDUCE PAIN 1. Mild analgesics intercept the pain stimulus at the source. This interception is created by the interference with the production of prostaglandins (Chemicals that cause pain, fever and swelling), i.e.: They REDUCE PAIN 2. Furthermore, they cause the blood vessels near the pain source to constrict, thereby REDUCING INFLAMMATION 3. Due to the reduction in the production of prostaglandins, the temperature of the person decreases, thus REDUCING FEVER ALSO: Aspirin, a mild analgesic, also has anti blood coagulation properties, and this is used in the treatment of heart attacks and strokes. EXAMPLES OF MILD ANALGESICS: Aspirin Ibuprofen Paracetamol D.3

IBUPROFEN ASPIRIN D.3 ACETAMINOPHEN

STRONG ANALGESICS Strong analgesics are more “radical” than the mild analgesics, and it is this property that makes them so restricted in usage. Strong analgesics prevent the transmission of the pain by binding with the pain receptors in the brain and blocking the communication of pain signals between brain cells. They also mimic the body’s own natural painkillers (namely endorphins and encephalin), ergo producing a sense of well being. EXAMPLES OF STRONG ANALGESICS INCLUDE: Heroin Codeine Morphine D.3

STRONG ANALGESICS D.3

D.3.2 Describe the use of derivatives of salicylic acid as mild analgesics, and compare the advantages and disadvantages of using aspirin and paracetamol (acetaminophen) Objectives: 3 D.3

SYNTHESIS OF ASPIRIN USING SALICYLIC ACID Salicylic acid reacts in the following manner to form aspirin: Salicylic Acid + Acetic Anhydride  Acetylsalicylic acid + Acetic Acid C7H6O3 + C4H6O3  C9H8O4 + C2H4O2 D.3

ASPIRIN ASPIRIN is considered a NSAID (Non-steroidal Anti-inflammatory drug), which can help treat “headaches, toothaches and sore throats… [as well as minimize] fever…and inflammation.” (Brown and Ford 341) Being a mild analgesic, aspirin prevents the formation of prostaglandin at its source and stops the transmission of the pain stimulus to the brain. D.3

STRUCTURE OF ASPIRIN ASPIRIN contains: A benzene ring A carboxylic acid group An ester group D.3

ADVANTAGES OF ASPIRIN It minimizes the coagulation of blood, and is thus given to individuals with the risk of a heart attack or stroke. It helps to relieve the symptoms of arthritis and rheumatism. It is non-addictive. D.3

Disadvantages OF ASPIRIN It causes bleeding in the lining of the stomach. It may also cause the formation of ulcers on the lining of the stomach. It is associated with bronchial asthma. Children under the age of twelve, who have been consuming Aspirin on a regular basis, have been associated with Reye’s disease. Reye’s disease is a fatal disease of the liver and the brain with symptoms of vomiting, lethargy, irritability, and confusion. Overdose of aspirin causes acidosis caused due to a lowering of the pH of the blood. D.3

PARACETAMOL (ACETAMINOPHEN) Acetaminophen is a pain killer, which is similar to aspirin, however does not act as an anti-inflammatory. It acts by minimizing the production of prostaglandin in the brain, while the production of prostaglandins in the rest of the body remain unaffected. It is rather safe for consumption by adults and children alike. D.3

STRUCTURE OF PARACETAMOL PARACETAMOL contains: A benzene ring A hydroxy group An amide group D.3

ADVANTAGES OF PARACETAMOLS Advantages include: It reduces fevers caused by the cold or the flu. It helps relieve pains caused in the muscles, like menstrual cramps, and also joint aches. It is not addictive. It is a very safe analgesic. D.3

DISADVANTAGES OF PARACETAMOLS They are ineffective in reducing inflammation. Paracetamol is a safe analgesic, however, if overused, can cause kidney and liver damage, and also brain damage, or in some cases, death. D.3

IBUPROFEN Ibuprofen is in a group of drugs called non-steroidal anti-inflammatory drugs (NSAIDs). It works by reducing hormones that cause inflammation and pain in the body. Ibuprofen is used to reduce fever and treat pain or inflammation caused by many conditions such as headache, toothache, back pain, arthritis, menstrual cramps, or minor injury. D.3

STRUCTURE OF IBUPROFEN IBUPROFEN contains: A benzene ring A carboxylic acid group D.3

ISOMERS OF IBUPROFEN IBUPROFEN has optical isomers. (Only the HL people know what this is, so SL people DO NOT PANIC.) This is due to the presence of a Chiral carbon. (Do we remember what that is?) D.3

D.3.3 Compare the structures of morphine, codeine and diamorphine (heroin, a semi-synthetic opiate). Objectives: 3 D.3

Cases of pain, e.g.: Heart attacks, Injuries and sometimes cancer. Morphine, Codeine and Diamorphine (heroin) are strong analgesics which are commonly classified as narcotics. They are extracted from the unripe seeds of the poppy plant and are called OPIATES. They are available only under prescription, and are given to individuals with SEVERE Cases of pain, e.g.: Heart attacks, Injuries and sometimes cancer. D.3

MORPHINE D.3

MORPHINE Morphine has the molecular formula C17H19NO3, and is chemically called “(5α,6α)-Didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol”. The structure contains an alcohol, a phenol, an amine and an ester group. D.3

MORPHINE VIDEO: http://www.youtube.com/watch?v=o9LmjkMp9Nc&feature=fvsr D.3

CODEINE D.3

CODEINE Codeine has the molecular formula C18H21NO3, and is chemically called “(5(,6()-7,8-didehydro-4,5-epoxy-3-methoxy-17-methylmorphinan-6-ol”. The structure contains a hydroxy group, a tertiary amine, an alkene group, a benzene ring and an ether group. D.3

DIAMORPHINE (HEROIN) D.3

DIAMORPHINE (HEROIN) Diamorphine, commonly known as heroin, is a semi-synthetic opiate, which interacts with pain receptor sites within the brain and blocks pain stimuli. It has a molecular formula C21H23NO5 , and is chemically named (5α,6α)-7,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol acetate. Its structure contains two ester groups, a tertiary amine group, a benzene ring, an alkene group and an ether group. D.3

CONVERSION OF MORPHINE TO DIAMORPHINE (HEROIN) Morphine is converted to heroin by reacting it with acetic anhydride or acetyl chloride. It is an esterification reaction, or it can also be labeled a condensation reaction. D.3

DIFFERENTIATING BETWEEN THE 3. Check this out: http://education.sdsc.edu/download/chemistry/analgesics.swf It shows us the differences in both, the molecular and the linear structures. D.3

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D.3.4 Discuss the advantages and disadvantages of using morphine and its derivatives as strong analgesics. Objectives: 3 D.3

Morphine and its derivative narcotics are the strongest painkillers and are available only under prescription. They are used to treat the pain caused by severe injury, and also by heart attacks. Some are even used to reduce labour pains during childbirth, as they are injected as an epidural. They act on specific areas of the brain and spinal cord that process pain signals from nerves throughout the body. D.3

SIDE EFFECTS OF NARCOTICS (GENERAL) SHORT TERM EFFECTS LONG TERM EFFECTS Dulling of pain Addiction and very strong withdrawal effects Euphoria Loss of libido Slow Nervous System Constipation Slow Heart Rate Disruption in menstruation Loss of cough reflex Loss of appetite Nausea Problems associated with the purchase of “street-drugs”, e.g.: Increased risk of AIDS from the sharing of needles. Overall slow down of biological systems. Overdose can lead to death, or a possibility of stroke. D.3

SIDE EFFECTS OF NARCOTICS (SPECIFIC) SERIOUS EFFECTS COMMON EFFECTS LESS COMMON EFFECTS Confusion Dizziness or lightheadedness Mood swings Severe drowsiness, dizziness, or weakness Nausea or vomiting False sense of analgesia (Euphoria) Slurred Speech Constipation Urinary retention Small, constricted pupils Drowsiness Jerky body movements (myoclonus) Cold and clammy skin Itching Hallucinations Slow breathing Sweating Seizures Loss of consciousness D.3

IB Chemistry Course Companion Google Image Search WORKS CITED http://www.herbs2000.com/medica/morphine.htm http://www.chemistry-drills.com/functional-groups.php?q=simple http://education.sdsc.edu/download/chemistry/analgesics.swf Unlisted Documents IB Chemistry Course Companion Google Image Search Sorry I didn’t feel like sticking to the MLA format. D.3

WARNING: Individuals with weak hearts, other health care issues, and severe paranoia or the hatred for the medical field et al… SHUT YOUR EYES! The content following this slide is GRAPHIC. D.3

The basic thing nobody asks is why do people take drugs of any sort The basic thing nobody asks is why do people take drugs of any sort? Why do we have these accessories to normal living to live? I mean, is there something wrong with society that's making us so pressurized, that we cannot live without guarding ourselves against it? -John Lennon D.3

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