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Opioid

Opioid

Uses

Prescription use

Opioids have long been used to treat acute pain (such as post-operative pain). They have also been found to be invaluable in palliative care to alleviate the severe, chronic, disabling pain of terminal conditions such as cancer, and degenerative conditions such as rheumatoid arthritis. Contrary to popular belief, high doses are not necessarily required to control the pain of advanced or end-stage disease, so long as the effects of tolerance (which means a physical reaction which makes the body immune to analgesic as well as mental effects of opiates, narcotics, and others) allow patients to often require a median dose in such patients being only 15 mg oral morphine every four hours (90 mg/24 hours). This means that 50% of patients manage on lower doses, and requirements can level off for many months at a time, depending on severity of pain, which varies. This is despite the fact that opioids have some of the greatest potential for tolerance of any category of drugs, which essentially means in many cases, opioids are a successful long-term care strategy for those in chronic pain as well as acute pain.In recent years there has been an increased use of opioids in the management of non-malignant chronic pain. This practice has grown from over 30 years experience in palliative care of long-term use of strong opioids which has shown that addiction is rare when the drug is being used for pain relief. The basis for the occurrence of iatrogenic addiction to opioids in this setting being several orders of magnitude lower than the general population is the result of a combination of factors. Open and voluminous communication and meticulous documentation amongst patient, caretakers, physicians, and pharmacists is one part of this; the aggressive and consistent use of opioid rotation, adjuvant analgesics, potentiators, and drugs which deal with other elements of the pain (NSAIDS) and opioid side effects both improve the prognosis for the patient and appear to contribute to the rarity of addiction in these cases. Unfortunately, in most countries the use of opioids is subject to complex legal regulations, which often impede proper medical use for pain control and thus result in unnecessary suffering for patients.

United States

The sole clinical indications for opioids in the United States, according to Drug Facts and Comparisons, 2005, are:

  • Moderate to severe pain, i.e., to provide analgesia or, in surgery, to induce and maintain anesthesia, as well as allaying patient apprehension right before the procedure. Fentanyl, oxymorphone, hydromorphone, and morphine are most commonly used for this purpose, in conjunction with other drugs such as scopolamine, short and intermediate-acting barbiturates, and benzodiazepines, especially midazolam which has a rapid onset of action and lasts shorter than diazepam(Valium) or similar drugs. The combination of morphine (or sometimes hydromorphone) with alprazolam(Xanax) or midazolam(Dormicum) or other similar benzodiazepines with or without scopolamine (rarely replaced with or used alongside Compazine, Zofran or other anti-nauseants) is colloquially called “Milk of Amnesia” amongst anesthesiologists, hospital pharmacists, physicians, radiologists, patients and others. The enhancement of the effects of each drug by the others is useful in troublesome procedures like endoscopies, complicated and difficult deliveries (pethidine and its relatives and piritramide where it is used are favoured by many practitioners with morphine and derivatives as the second line), incision & drainage of severe abcesses, intraspinal injections, and minor and moderate-impact surgical procedures in patients unable to have general anesthesia due to allergy to some of the drugs involved or other concerns.
  • Cough (codeine, dihydrocodeine, ethylmorphine (dionine), hydromorphone and hydrocodone, with morphine or methadone as a last resort.)
  • Diarrhea (generally loperamide, difenoxin or diphenoxylate; but paregoric, powdered opium or laudanum or morphine may be used in some cases of severe diarrheal diseases, e.g. cholera); also diarrhea secondary to Irritable Bowel Syndrome (Codeine, paregoric, diphenoxylate, difenoxin, loperamide, laudanum)
  • Anxiety due to shortness of breath (oxymorphone and dihydrocodeine only)
  • Opioid dependence (methadone and buprenorphine only)

In the U.S., doctors virtually never prescribe opioids for psychological relief (with the narrow exception of anxiety due to shortness of breath), despite their extensively reported psychological benefits, and the widespread use of opiates in depression and anxiety up until the mid 1950s. There are virtually no exceptions to this practice, even in circumstances where researchers have reported opioids to be especially effective and where the possibility of addiction or diversion is very low—for example, in the treatment of senile dementia, geriatric depression, and psychological distress due to chemotherapy or terminal diagnosis (see Abse; Berridge; Bodkin; Callaway; Emrich; Gold; Gutstein; Mongan; Portenoy; Reynolds; Takano; Verebey; Walsh; Way).

Use of opioids in palliative care

Indications for opioid administration in palliative care include:

  • “Any pain of moderate or greater severity, irrespective of the underlying pathophysiological mechanism.” Opioid analgesics have been prescribed for the treatment of chronic musculoskeletal pain, such as rheumatoid arthritis, osteoarthritis, and low back pain. There is a difference between physical dependence and addiction and tips are offered to physicians who are contemplating prescribing opioids for patients with chronic musculoskeletal pain. However, opioids are not first-line therapy but should be used as part of a comprehensive treatment plan that involves other medications and modalities, such as acetaminophen, aspirin, muscle relaxants, and antidepressants (because patients with chronic pain are often depressed).
  • Breathlessness / shortness of breath (The largest evidence base exists for morphine.)
  • Diarrhea (Loperamide is the most widely used as it does not cross the blood-brain barrier and acts only on smooth muscle, such as in the digestive tract.)
  • Painful wounds (Topical morphine in an aqueous gel can be an effective agent as it acts on opioid receptors in damaged tissue.)

Opioids are often used in combination with adjuvant analgesics (drugs which have an indirect effect on the pain). In palliative care, opioids are not recommended for sedation or anxiety because experience has found them to be ineffective agents in these roles. Some opioids are relatively contraindicated in renal failure because of the accumulation of the parent drug or their active metabolites (e.g. morphine and oxycodone). Age (young or old) is not a contraindication to strong opioids. Some synthetic opioids such as pethidine have metabolites which are actually neurotoxic and should therefore be used only in acute situations.

History

Non-clinical use was criminalized in the U.S by the Harrison Narcotics Tax Act of 1914, and by other laws worldwide. Since then, nearly all non-clinical use of opioids has been rated zero on the scale of approval of nearly every social institution. However, in United Kingdom the 1926 report of the Departmental Committee on Morphine and Heroin Addiction under the Chairmanship of the President of the Royal College of Physicians reasserted medical control and established the “British system” of control—which lasted until the 1960s; in the U.S. the Controlled Substances Act of 1970 markedly relaxed the harshness of the Harrison Act.

Before the twentieth century, institutional approval was often higher, even in Europe and America. In some cultures, approval of opioids was significantly higher than approval of alcohol.

Global shortage of poppy-based medicines

Morphine and other poppy-based medicines have been identified by The World Health Organization as essential in the treatment of severe pain. However, only six countries use 77% of the world’s morphine supplies, leaving many emerging countries lacking in pain relief medication. The current system of supply of raw poppy materials to make poppy-based medicines is regulated by the International Narcotics Control Board under the provision of the 1961 Single Convention on Narcotic Drugs. The amount of raw poppy materials that each country can demand annually based on these provisions must correspond to an estimate of the country’s needs taken from the national consumption within the preceding two years. In many countries, underprescription of morphine is rampant because of the high prices and the lack of training in the prescription of poppy-based drugs. The World Health Organization is now working with different countries’ national administrations to train healthworkers and to develop national regulations regarding drug prescription to facilitate a greater prescription of poppy-based medicines.

Another idea to increase morphine availability is proposed by the Senlis Council, who suggest, through their proposal for Afghan Morphine, that Afghanistan could provide cheap pain relief solutions to emerging countries as part of a second-tier system of supply that would complement the current INCB regulated system by maintaining the balance and closed system that it establishes while providing finished product morphine to those suffering from severe pain and unable to access poppy-based drugs under the current system.

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