Analgesic

Analgesic is a drug or compound that is used to relieve pain or pain without losing consciousness. Awareness of pain consists of two processes, namely the acceptance of pain stimuli in the brain and emotional reactions and the individual against these stimulants. Barrier of pain medication (analgesic) affect the first process to heighten awareness of the feelings of pain threshold, while narcotics suppress psychis reactions caused by pain stimuli.

The pain in most cases only a symptom, whose function is to protect and give the alarm about the presence of disturbances in the body, such as inflammation (rheumatoid, gout), germ infections or muscle spasms.
The cause of pain is mechanical stimuli, physical, or chemical that can cause tissue damage and release of certain substances called mediators of pain that is located on free nerve endings in the skin, mucous membranes, or tissue- tissues (organs) other. From this place the stimulus flowed through sensory nerves to the Central Nervous System (CNS) through the spinal cord to the thalamus and then to the center of a big pain in the brain, where the stimulus is felt as pain. Mediators of pain the most important is histamine, serotonin, plasmakinin-plasmakinin, and prostaglandin-prostagladin, and potassium ions.
Based on the occurrence of pain, the pain can be combated in several ways, namely:

1. Hinder the formation of stimulus in the peripheral pain receptors, by peripheral analgesics or local anesthetic.
2. Hinder the distribution of pain stimuli in sensory nerves, for example by local anesthetic
3. Blockade of central pain in the Central Nervous System with central analgesics (narcotics) or general anesthetic.

In the treatment of pain with analgesics, psychological factors play a role, such as patience and resources of individuals receiving pain from the patient. In general analgesic is divided into two groups, namely non-narkotinik analgeti or non-opioid analgesics or integumental analgesics (eg asetosal and paracetamol) and narcotic analgesics or opioid analgesics or visceral analgesics (eg morphine).

Narcotics analgesics
These substances have a strong power blocking pain once the level of employment is located in the Central Nervous System. Generally reduced consciousness (relieving properties and lull) and cause uncomfortable feelings (euphoria). Can lead to tolerance and habits (habituation) as well as psychological and physical dependence (addiction addiction) with abstinensia symptoms when treatment is stopped. Because of the dangers of this addiction, then most of central analgesics such as narcotics included in the Narcotics Act and its use is strictly controlled .
Chemically, these drugs can be divided into several groups as follows:
1. Natural and synthetic opiate alkaloids morphine and codeine, heroin, hidromorfon, hidrokodon, and dionin.
2. Morphine substitutes consisting of:
a. Pethidine and its derivatives, fentanyl and sufentanil
b. Methadone and its derivatives: dekstromoramida, bezitramida, piritramida, and d-ptopoksifen
c. Fenantren and its derivatives also include pentazosin levorfenol.
Morphine antagonists are substances that can fight the side effects of narcotic analgesics without reducing labor analgesic and is mainly used in overdose or intoksiaksi with these medications. These substances themselves are also efficacious as an analgesic, but can not be used in therapy, because he himself cause side effects similar to mrfin, including respiratory depression and psychotic reactions. Frequently used is nalorfin and naloxone.
Side effects of morphine and other central analgesics at usual doses are gastric disturbances, intestinal (nausea, vomiting, obstipasi), as well as other central effects such as restlessness, sedation, drowsiness, and mood changes to euphoria. At higher doses the effects occurred more dangerous is respiratory depression, decreased blood pressure, and impaired blood circulation. Finally, can occur coma and respiratory standstill.

Effects of morphine on the Central Nervous System in the form of analgesia and narcosis. Analgesia by morphine and other opioids has been incurred before the person is sleeping and analgesia often occur without sleep. Small doses of morphine (15-20 mg) caused euphoria in patients who are suffering pain, sorrow and anxiety. Conversely, the same dose in normal people often creates a feeling of dysphoria worry or fear is accompanied by nausea, and vomiting. Morphine also cause drowsiness, can not concentrate, difficulty thinking, apathy, decreased motor activity, decreased visual acuity, ektremitas tersa weight, body feels hot, hot itchy and dry mouth, respiratory depression and miosis. The hunger is lost and can not always accompanied by vomiting nausea. In a quiet environment people are given a therapeutic dose (15-20 mg) of morphine will fall asleep quickly and soundly with a dream, slow breath and miosis.
Between pain and analgesic effects (respiratory depressant effects as well) contained morphine and other opioid antagonism, that pain is an antagonist faalan for analgesic effect and respiratory depressant effects of morphine. When pain is experienced for some time before administration of morphine, analgesic effects of these drugs are not so great. Conversely, if the stimulus of pain inflicted after reaching maximum analgesic effect, morphine dose required to abolish the pain was much smaller. Patients who are experiencing severe pain and require mofin with large doses to relieve pain, respiratory depression can be resistant to morphine. But when the pain was suddenly gone, then most likely symptoms of respiratory depression by morphine.

Peripheral analgesics (non-narcotic)
Drugs this drug is also called peripheral analgesics, because it does not affect the Central Nervous System, do not lose consciousness or lead to addiction. All the peripheral analgesic antipyretic also have work: lower body temperature in febrile conditions, it is also known antipyretic analgesics. Usefulness based on the excitement of the heat regulating center in the hypothalamus, resulting in peripheral vasodilatation (in skin) with the increase in spending a lot of heat and accompanied by the release of sweat.
Chemical classification of peripheral analgesics are as follows:
1. salicylates, salicylate, Na-salicylate, asetosal, salisilamida, and benirilat
2. Derivatives of p-aminofenol: fenasetin and paracetamol
3. Derivatives pirozolon: antipirin, aminofenazon, dipiron, phenylbutazone danturunan-derivatives
4. Derivatives antranilat: glafenin, mefenamic acid, and acid nifluminat.

Side effects that usually emerge are disturbances of the stomach-intestine, blood damage, liver damage, and kidney as well as allergic skin reactions. These side effects occur mainly on the use of long or in large doses, then you should not use these analgesics continuously.

Analgesic-Antipyretics
Analgesics are drugs that reduce or eliminate pain without losing consciousness. While antipyretics is a drug that can lower high-temperature body. Thus, analgesic-antipyretic drug dalah which reduces pain and simultaneously reduce high body temperature.
As a mediator of pain, among others, are as follows:
1. Histamine
2. Serotonin
3. Plasmokinin (including bradykinin)
4. Prostaglandins
5. Potassium Ion

Analgesics given to patients to reduce pain that can be caused by various stimuli mechanical, chemical, and physical that goes beyond a certain threshold value (the value of pain threshold). The pain is caused by the release of pain mediators (eg bradykinin, prostaglandins) from the damaged tissue which then stimulates pain receptors in the peripheral nerve endings or elsewhere. From these places later excitatory pain forwarded to the pain center in the cerebral cortex by sensory nerves through the spinal cord and thalamus.