Opioid medications are generally reserved for moderate-to-severe pain. Codeine, dihyrocodeine, hydrcodone and oxycodone are commonly prescribed with combination of aspirin, acetaminophen or ibuprofen to manage acute, dental and post-operative pain in dental practice.
Brand Name: Morphine Sulphate 10mg/ml inj ;Morcontin 10, 30, 60, 100 mg CR tabs;30 -100mg BD.
Morphine acts as an anesthetic without decreasing consciousness and it is one of the most powerful analgesics. However it also suppresses the respiratory system and high doses can cause death by respiratory failure.
Its analgesic properties are related to the ability of the molecule to fit into and block a specific receptor site on a nerve cell. This eliminates the action of the pain receptor, preventing the pain signals from reaching the brain. This is similar to the way in which the body's natural painkillers (endorphins and enkaphalins) work.
Morphine can be used:
Avoid using for-
It is accidental or seen in drug abusers. 50mg of morphine produces serious toxicity.Human lethal dose is 250 mg.
Stupor or coma, flaccidity, shallow and occasional breathing, cyanosis, pinpoint pupils, fall in BP and shock, convulsions may be seen in few, pulmonary edema occurs at terminal stage, death is due to respiratory failure.
Treatment:Tolerance to the analgesic effects of morphine is fairly rapid. Morphine is a highly addictive substance, as it can cause psychological and physical dependence as well as tolerance, with an addiction potential identical to heroin.
WithdrawalThe withdrawal symptoms associated with morphine addiction are usually experienced shortly before the time of the next scheduled dose (usually between 6–12 hours).
Early symptoms include watery eyes, insomnia, diarrhea, runny nose, yawning, dysphoria and sweating and in some cases a strong drug craving. Severe headache, restlessness, irritability, loss of appetite, body aches, severe abdominal pain, nausea and vomiting, tremors and even stronger and more intense drug craving appear as the syndrome progresses. Severe depression and vomiting are very common.
During the acute withdrawal period systolic and diastolic blood pressure increase, usually beyond pre-morphine levels and heart rate increases, which could cause a heart attack, blood clot or stroke.
Chills or cold flashes with goose bumps ("cold turkey") alternating with flushing (hot flashes), kicking movements of the legs and excessive sweating are also characteristic symptoms. Severe pains in the bones and muscles of the back and extremities occur, as well as muscle spasms.
Major withdrawal symptoms peak between 48 and 96 hours after the last dose and subside after approximately 8 to 12 days.
Treatment:Consist of withdrawal of morphine and substitution with oral methadone followed by its gradual withdrawal.
Advanced respiratory insufficiency, bronchial asthma, raised intracranial pressure.
Common effects include euphoria, itching, nausea, vomiting, drowsiness, dry mouth, miosis, orthostatic hypotension, urinary retention, depression and constipation.
Brand Name: Pethicine HCl 100mg/2ml inj; 50,100 mg tab.
A pethidine congener is more potent than morphine both as analgesia as well as respiratory depressent.
Transdermal fentanyl has become available for use in cancer or other chronic pain for patients requiring opioid analgeisa.
Methadone also binds to the glutamatergic NMDA (N-methyl-D- aspartate) receptor, and thus acts as a receptor antagonist against glutamate. Glutamate is the primary excitatory neurotransmitter in the CNS.
Acting as an NMDA antagonist may be one mechanism by which methadone decreases craving for opioids and tolerance. It has been proposed as a possible mechanism for the treatment of neuropathic pain.
It reduces and/or eliminates the use of heroin and criminality associated with heroin use. It allows patients to improve their health and social productivity.
In addition, enrollment in methadone maintenance has the potential to reduce the transmission of infectious diseases associated with heroin injection, such as hepatitis and HIV.
The principal effects are to relieve narcotic craving, suppress the abstinence syndrome, and block the euphoric effects associated with heroin. Methadone maintenance has been found to be medically safe and non-sedating. It is also indicated for pregnant women addicted to heroin.
Methadone linctus, which is about one-third the concentration of the liquid methadone used for opioid maintenance, is used where available and approved as a cough syrup for violent coughing. Narcotic cough suppressants are very useful against dry, unproductive coughing, especially that which persists after an illness and/or is a manifestation of recurring bronchitis, causes pain in the chest and/or prevents the patient from sleeping.
It is well tolerated and side effects are dizziness, nausea, sleepiness, dry mouth and sweating. Safer in patients with compromised cardiovascular function as heamodynamic results are minimal.