1. Analgesics
Sandy Kulkarni

2. Analgesics Analgesics are common pain relievers.
Many analgesics also have antipyretic properties as well. They can be used to reduce fever
Some analgesics are also anti-inflammatory drugs as well

3. Classification of Analgesics
Strong
Analgesics
Mild
Analgesics
Opium
Aspirin
Ibuprofen
Heroin
Codeine
Acetaminophen

4. Mild Analgesics
Mild Analgesics include over-the-counter pain relievers and fever depressants.
Examples of mild analgesics include Aspirin, acetaminophen, and ibuprofen

5. Aspirin Aspirin is a derivative of salicyclic acid
Salicyclic acid was found in the bark of the willow tree and was used as a pain reliever and as a way to relieve fever symptoms of malaria
Salicyclic Acid
Aspirin

6. Aspirin
In 1899, Felix Hoffman, a chemist from the Bayer Company, developed a low-cost process to synthesize an ethanoate ester of salicyclic acid, called aspirin
In the synthesis of Aspirin, the ethanoic acid forms an ester with the alcohol group on the second carbon

7. Aspirin
Aspirin is believed to inhibit the enzyme, Prostaglandin synthase which is formed at the site of an injury.
This inhibits the production of prostaglandins which produce fever and swelling as well as transmitting pain signals to the brain.

8. Aspirin
Aspirin is able to reduce pain and fevers and dilate blood vessels
Aspirin enlarges blood vessels which helps prevent blood clots.
This vasodilation of the surface blood vessels also allows an increase of heat released which lowers the temperature of a fever
Aspirin is also taken to prevent recurring heart attacks
It may also be effective in preventing prostrate cancer

9. Side Effects of Aspirin
Aspirin can irritate the stomach lining which may lead to ulcers
If aspirin is used over long periods of time, it may lead to problems with blood clotting
An overdose on aspirin, such as the case with some arthritis sufferers, may lead to dizziness, ringing in the ears, gastrointestinal problems, mental confusion, and bleeding.
Some people are allergic to aspirin leading to bronchial asthma
In children under 12 Aspirin has been linked to Reye’s syndrome

10. Other Mild Analgesics Acetaminophen (Paracetamol)
Commonly sold as Tylenol
Ibuprofen
Commonly sold under the name Advil

11. Acetaminophen
Acetaminophen is a pain reducer, such as Tylenol but does not reduce inflammation
When taken at recommended doses, it has negligible side effects
It’s low level side effects make it favorable to arthritis patients and children
Overuse and overdoses can lead to acute liver failure and kidney damage

12. Ibuprofen
Ibuprofen is a more powerful pain reliever than aspirin in high doses, but is inferior for anti-inflammation
Side effects include gastrointestinal bleeding and irritation
Can aggravate kidney problems

13. Strong Analgesics Only Available by prescription
Used to relieve severe pain associated with injuries, heart attacks, or chronic diseases such as cancer
Most strong analgesics are derived from the opium poppy or synthetically produced
Basically three types: Natural, semi-synthetic, and synthetic

14. Morphine Naturally occurring in the poppy- Only needs to be isolated
Very strong pain reliever but also very addictive (2nd to Heroin)
Usually injected but can be smoked, sniffed or swallowed
Commonly used in hospitals
Large illegal street culture

15. Codeine Most commonly used strong analgesic
Similar to Morphine except for the replacement of a (OH-) group for (OCH3) group
Commonly used with Tylenol as a more mild analgesic
1/6 as strong as Morphine and less addictive

16. Heroin
Originally sold as cough suppressant and pain killer10 times stronger than Morphine
Incredibly addictive (many times, other strong analgesics are needed for withdrawal)

17. Heroin
Synthesized from morphine in a esterification reaction with acetyl chloride
It is absorbed by the brain very quickly resulting in a potent high
Many other problems are associated with heroin addiction including as prostitution and AIDS.

18. Other Synthetic Strong Analgesics
Vicodin
Is solution of acetaminophen and hydrocodone (the latter being the stronger)
Hydrocodone is addictive and can cause highs.
Usually taken orally
Stronger than codeine but not as strong than Morphine

19. Synthetic Strong Analgesics (Opioids)
The active area of morphine has been identified and can be synthesized.
This has produced many synthetic analgesics and has allowed scientists to eliminate some of the harmful side effects of more natural analgesics.

20. Demerol Demerol (Meperidine)
Used for moderate to severe pain and to stop muscle spasms.
Usually injected or taken orally.

21. Methadone Compared to most strong analgesics it is weaker.
Has been synthesized to not have euphoric properties and mild withdrawal effects but is still addictive.
Used as an analgesic but most commonly to help in the withdrawal for Heroin addicts.

22. Mechanism of Strong Analgesics
The human body contains “natural opiates” in the brain called endorphins
These are produced in the body during extreme conditions such as “running high” and extreme injuries.
When these are absorbed by receptors in the brain the body feels analgesia and the pain is reduced.

23. Mechanism of Strong Analgesics cont.
Opiates derived from the poppy act in the same way as endorphins but are not natural to the human body.
The “high” is produced because of the absorption of opiates is quicker than endorphins
Drugs such as naloxone act to fill the receptors in the brain but are not analgesics and thus are used to prevent overdoses on analgesics.
Endorphins are not used as analgesics because the cannot be stored and are unstable.

24. Side Effects of Strong Analgesics
Short term
Dulling of Pain
Euphoria
Slow Nervous system
Slowed heart rate
Loss of cough reflex
Nausea
Overdoses can lead to death
Possibility of stroke
Overall slowdown of biological systems
Long Term
Addiction and very strong withdrawal effects
Constipation
Loss of libido
Disruptions in menstruation
“Cross-tolerance”
Loss of appetite
Problems associated with buying street drugs i.e. sharing needles AIDS and prostitution.

25. Local Anesthetics -- Cocaine
Cocaine used in 1885 as a local anesthetic.
Extracted from the plant Erythoxylum coco
([1R-(exo,exo)]-3-(Benzoyloxy)-8-methyl-8-azabicyclo[3.2.1]octane-2-carboxylic acid methyl ester

26. History of Cocaine
Coca leaves have been chewed by South American Indians for thousands of years. There were used to induce feelings of euphoria
Was banned by Spanish settlers in the 1500s but the ban was repealed when it became apparent that slaves worked harder while on it
United States cocaine was used in soft drinks until it was classified as narcotic in 1914
Clinically used as a local anaesthetic for eye operations and in modified synthetic forms for dental treatment (novocaine) and sore throats (benzocaine)

27. Cocaine
The leaves of the coca plant contain 0.6% - 1.8% alkaloidal cocaine
To extract, cocaine leaves are soaked in kerosene and sulfuric acid
HCl is added creating cocaine hydrochloride, which can be extracted as powdery flakes or rocks

28. Clinical Action
Acts as a reuptake blocker for the monoamines dopamine, norepinephrine and serotonin
interacts with serotonin and muscarinic acetylcholine receptors and the sodium channels
influence on the axonal voltage-gated sodium channels that provides cocaine's local anaesthetic properties

29. Effects of Cocaine Physiological Subjective Increased heart rate
Increased respiration rate
Increased body temperature
Increased blood pressure
Pupil dilation
Subjective
Euphoria
Increased sociability
Increased energy
Hyper vigilance

30. Derivatives of Cocaine
Cocaine is too addictive and in appropriate for medicinal use
Two derivatives of cocaine are widely used as local anesthetics
Procaine or Novacaine
Lidocaine

31. Procaine (Novacaine)
Novacaine
Principal use in dentistry for temporary numbing of mouth area
First synthesized in 1905 and was the first injectable man-made local anesthetic
Restricts blood vessels, reducing bleeding

32. Lidocaine Sodium channel blocker
Administered parenterally for ventricular arrhythmias, subcutaneously for minor surgical procedures, and topically to mucosal surfaces prior to invasive procedures