Methadone hydrochloride is an effective, inexpensive, and relatively safe opioid to use in the treatment of patients with chronic pain. It is especially effective in management of pain during the final stages of life, as it is the only long-acting analgesic available in liquid form. However, because methadone has a long half-life, individual wide variations, and potential for accumulation and overdosage, physicians must judiciously and conscientiously prescribe it. Also, they should closely monitor patients during the titration phase and educate them with regard to basic pharmacologic properties and potential side effects. A plan to start at low doses and proceed slowly is applicable to methadone.
Chronic pain is one of the most common conditions for which people seek medical treatment; it affects more than 85 million Americans. In end-of-life care, in which the primary focus is the reduction or elimination of suffering, a significant number of patients still suffer with uncontrolled pain. In recent years, healthcare consumers have become more sophisticated, demanding better pain control. Therefore, physicians need to be familiar and competent with the various treatment options and pharmacologic management of their patients with chronic pain.
Although the primary responsibility of physicians is to nurture the physical and psychological well-being of their patients, it is also important that they serve as stewards of financial resources. In the past several years, there has been resurgence in the understanding of the pharmacologic and pharmacokinetic properties of methadone hydrochloride. This resurgence, coupled with methadone's low cost, has led to increased use of this agent in the treatment of chronic pain.
Methadone is a synthetic opioid agonist developed in the late 1940s. Historically, it has been used in the treatment of patients with narcotic addiction and heroin maintenance since the 1960s. Although substantial information exists regarding such use of methadone, only limited data are available with respect to pain management. It is only within the past decade that there has been a renewed focus on its use in the treatment of patients with chronic pain.
Initial interest in methadone for pain management emerged in the care of terminally ill patients with cancer, but methadone recently has been gaining recognition in management of nonmalignant
pain. Methadone is achieving greater acceptance in end-of-life care because of its unique characteristic as the sole long-acting opioid in liquid form. Its wide spectrum of absorption and formulations allows administration using every route available: oral, sublingual, rectal, subcutaneous, intramuscular, intravenous, epidural, intrathecal, and percutaneous endoscopic gastrostomy (PEG) tube.
By John F. Manfredonia, DO
