Opioid analgesics do not have antipyretic or anti-inflammatory properties. They exert a suppressive effect on the central nervous system.
Morphine and similar are strong painkillers.
- Natural (morphine, codeine)
- Semi-synthetic (pentazocine, nalorphine, butarphanol, etorphine)
- It can be synthetic (Meperidine, diphenoxylate, fentanyl, carfentanil, Methadone, propoxyphene etc.).
Opioid analgesics do not have antipyretic or anti-inflammatory properties. They exert a suppressive effect on the central nervous system.
Mechanisms of action :
Opioids exert their effects by binding to four specific receptors (mu, kappa, sigma and delta). They show different effects depending on the type of opioid and the receptor to which it binds. These:
- Analgesic effect: It reduces the perception of pain in the central nervous system.
- Sedative effect: It decreases the level of consciousness and mental activity.
- Anxiolytic effect: It prevents anxiety.
- Euphoric effect: It has a psychological healing effect.
- Antitussive effect: It reduces the cough reflex.
- Anti-emetic effect: Initially it causes nausea and vomiting, but then it prevents vomiting by blocking the vomiting center.
- Respiratory depressant: Suppresses the respiratory center.
- Miotic effect: It makes the pupils dilate.
- Addictive effect: Develops tolerance and dependence.
General properties of opioids:
- They can be absorbed through the gastrointestinal tract, nose, skin, muscle or lungs. However, their absorption is less when taken orally compared to intravenous administration.
- They can show effects ranging from mild numbness to deep coma in the central system.
- They are more or less addictive.
- Tolerance may develop with prolonged use. That is, higher doses of opioids may be required to achieve the same effect.
- At the end of the treatment or if it is interrupted, withdrawal symptoms may develop if abrupt discontinuation occurs.
- Concomitant use with antidepressant drugs may increase respiratory depression.
- It requires careful use in terms of side effects.
- Illegal use is high.
Usage areas:
Opioids are used in many diseases. These:
- Painkillers: Treatment of moderate or severe post-operative pain, treatment of non-cancer chronic pain (headache, severe migraine pain, fibromyalgia, etc.), treatment of cancer pain.
- Cough: Codeine is used to suppress cough in low doses, but its use is not recommended in recent years, especially in children.
- Diarrhea: Opioid (loperamide) is used in the treatment of diarrhea in irritable bowel syndrome.
- Shortness of breath: Opioids are used in the treatment of shortness of breath, especially in cancer or advanced lung diseases.
Side effects:
- Addiction: Withdrawal symptoms develop when the drug cannot be reached. It can be physical or psychological addiction.
- Tolerance: Indicates that the body adapts to the opioid, requiring higher doses to have the same effect. It is common in patients who use opioids for a long time.
- Nausea, vomiting,
- Numbness,
- Itching,
- Constipation,
- Respiratory depression,
- Distractibility,
- Sleeping state.