Letters

Opioids in chronic non-malignant pain

Opioids can cause addiction even in patients with pain

Chronic pain should not be undertreated

Don't forget methadone for chronic pain

Opioids can cause addiction even in patients with pain

EDITORMcQuay in his editorial says that we know that if the opioid sensitive pain later resolves treatment can be stopped without patients becoming addicts.¹ Does he mean that there is little or no chance of addiction or that occasionally the patient will not become addicted? There is no reference given for this statement.

As a medical student (long before evidence based medicine) I was led to believe that in this situation there was very little risk of addiction. But my faith in this comforting idea was shaken by my experience of being involved with the management of a mountaineer who had severe frostbite of the hands and feet in Nepal 40 years ago. When in hospital in Kathmandu the severe pain in his feet could only be controlled by opioids (pethidine). In discussions about the continued use of this drug I took a relaxed attitude because of the teaching I had received. The man later had to have both legs amputated below the knee. During this time he became thoroughly addicted to pethidine. The management of drug addition was less developed in those days and he decided to come off "cold turkey." His experience in achieving this is graphically described in his book, No Place for Man.²

From what we know of the effect of opioids in downregulating the opioid receptors it is hardly surprising that continued use of high doses of opioids even in opioid sensitive pain relief is likely to lead to addiction. The outcome, however, may well depend on the dose and route of administration. I agree with McQuay that we urgently need more hard data.

James S Milledge, physician emeritus. 
Northwick Park Hospital, Harrow HA1 3UJ

Chronic pain should not be undertreated

EDITORI am a patients' advocate and literature researcher, not a physician. In internet community service work I have corresponded with hundreds of patients with chronic face pain. Many of these have diagnosed facial neuralgias or neuropathies. Many report that one or more doctors have refused to treat them with opioids, even on a trial basis. Some report having been accused of drug seeking behaviour simply for committing the offence of requesting treatment with drugs that they know from experience are effective for them. In the health insurance system in the United States the consequences of such a comment in a patient's medical record can be horrendous.

I recognise that treatment with opioids is generally less effective for the categories of pain that I see than for the general population. But from long exposure to online discussions between patients themselves, I know that some people do get relief from individual opioids or "cocktails" tailored by a pain specialist. I am forced by this experience to condemn outright the refusal of many medical professionals to even try such measures, in the absence of other effective medical or surgical remedies. I heartily endorse research to assess factors related to patients and efficacy of drugs, as suggested by McQuay.¹

It is long past time to put to rest the myth that prescribed pain drugs create addiction problems on the street. This issue should be readily susceptible to simple retrospective studies. How many convicted drug offenders in the United States or United Kingdom have been prescribed opioids by a doctor? Surely these numbers are known or can readily be derived?

Drug offenders tend to come from population cohorts that are among the least served by medical caregivers. In the United States, the evidence is strong that medical practice for pain management is about to undergo a popular revolution. What a shame that the process had to be forced by patients' lawsuits, rather than proceeding from simple common sense and compassion on the part of professional caregivers. If you are one of those doctors who continue to withhold pain management measures from your patients, then I suggest that you need refresher training in current practice for pain management.

Richard A Lawhern, network contact. 
Trigeminal Neuralgia Association (US), Sterling, VA 20165, USA lawhern{at}erols.com

Don't forget methadone for chronic pain

EDITORMcQuay in his editorial says that the use of opioids for chronic non-malignant pain can be messy, but this need not be so.¹ The risks and benefits of opioids are well attested. The study of fentanyl patches versus long acting morphine is an imperfect comparison of one expensive opioid delivery system with another.² McQuay chose manufacturers' recommendations over numerous clinical alternatives. Medical trials are often represented as a race with a clear winner. In this case, the winner happens to be the product of the company sponsoring the trial. McQuay's question on treating pain responsive to opioids presupposes that a patient has already tried opioids. We could instead ask whether doctors should deny opioids to a patient who seems to benefit from them? Withdrawing such drugs may be unwise or even unethical.

Differences between various opioids are to be expected because their effects are individual and doses never exactly comparable. Since this trial was not blind, the claim of modest advantages for fentanyl is not scientifically robust, as McQuay points out. Some reported improvements may also stem from the novelty factor, with a patch delivery system. Transdermal patches have certain benefits, but they also have problems. Dose adjustments are not easy, disposal can be hazardous, and adhesion can be a problem, especially in countries where people usually bathe daily. The choice of drug for chronic pain should not ignore the safety profiles of traditional opioids such as oral methadone, morphine, or codeine. From its use in addiction, methadone has exemplary long term safety data. It is also taken once daily. Although it is a cheap drug and perhaps of less interest to drug companies, methadone can be highly effective for chronic pain.

Clinicians should always consider the safest and most effective drug initially, moving to other options if problems arise. Cost is also a factor, especially in conditions requiring long term pharmacotherapy. Any stigma from methadone or morphine quickly vanishes when these drugs are used appropriately. Fentanyl patches should probably not be used as first line treatment. Likewise, long acting morphine, which is expensive and generally administered twice daily, should probably be second line treatment to methadone. If methadone is found to be unsatisfactory, buprenorphine, oxycodone, morphine (long or short acting), and fentanyl are all viable alternatives. Despite the best science, the use of such opioids is still often based on trial and error.

Andrew Byrne, general practitioner. 
Drug and Alcohol, Redfern, New South Wales, 2016, Australia

AB makes a proportion of his income from treating addiction and pain management patients. No tobacco sponsorship. No cruel animal experiments performed in this practice.