Safe prescribing - benzodiazepines

Safe prescribing: benzodiazepines

Following recent high profi le coverage of inappropriate prescribing, Dr Muiris Houston reminds doctors of their responsibilities and the official guidelines surrounding benzodiazepines

“Mother’s little helpers” and “sleepers” were just some of the benign names bestowed on the benzodiazepine group of drugs when they were first marketed in the 1960s. With no initial concerns over dependence, the drugs were widely prescribed as a magic solution for insomnia and anxiety.

Benzodiazepines are a family of drugs used as hypnotics, anxiolytics, tranquillisers, anticonvulsants, for pre-medication and for intravenous sedation. Short-acting ones are used as hypnotics, longer acting ones as hypnotics and tranquillisers, and those with high lipid solubility act rapidly if given intravenously.

The drugs were widely prescribed as a magic solution for insomnia and anxiety

Most of the disadvantages of benzodiazepines have resulted from inappropriate long-term use; this has earned them a poor reputation, particularly as drugs of dependence. Adverse effects include psychomotor impairment, especially in older people. With long-term use, tolerance, dependence and withdrawal effects become significant clinical problems. Research has also linked benzodiazepine use to an increased risk of falls in older people.

In the spotlight

Doctors’ prescribing of hypnotics and anxiolytics has come under the microscope recently in Ireland. A Dublin GP faced five allegations of poor professional performance after he allegedly over-prescribed benzodiazepines for patients with anxiety and insomnia. A Medical Council fitness to practise hearing was told a GP in Dublin prescribed the psychoactive drug for four patients over extended periods and at up to four times the recommended dose.

The allegations against him included that he failed to comply with Department of Health guidelines on prescribing the drugs. He also allegedly failed to make any or adequate enquiries as to whether any of the patients were being treated by another GP, failed to arrange for referral to a specialist substance misuse practitioner or drug treatment centre, and failed to prescribe the most appropriate medicine to suit the patients’ condition and/or best interests.

Can benzodiazephines shorten your life?

Earlier this year some research from the US caused quite a splash in the media with headlines proclaiming benzodiazepines caused premature death. Researchers tracked the survival of more than 10,500 people with a range of underlying conditions, who were prescribed sleeping pills for an average of 2.5 years between 2002 and 2007.

They then compared this group’s survival with a similar group who had not been taking sleeping pills over the same period and found some sleeping pills were associated with a four-fold increased risk of death. The authors also said they had found a greater prevalence of cancer among those taking the pills.

Despite the headlines, the research did not find that hypnotic drugs cause premature death. At best, it found an association and even at that, the research was open to some methodological criticism.

The research did not find that hypnotic drugs cause premature death

More recently, a Cork GP voluntarily gave an undertaking to the High Court not to prescribe sedatives and tranquillisers to patients, pending the outcome of an inquiry by the Medical Council into his prescribing policy. The Medical Council confirmed the GP has voluntarily undertaken to both the Medical Council and the High Court not to prescribe benzodiazepines and opiates pending an adjudication by the Medical Council of allegations regarding his prescribing. Health Service Executive South confirmed that he had decided to temporarily close his practice.

Best practice

Prescribing guidelines for benzodiazepines make it clear these drugs should normally not be prescribed for periods greater than two weeks. And while it is acknowledged that there are some patients who are dependent upon benzodiazepines, the guidelines advise that in these cases only small quantities of the drug should be issued at any one time.

Prescriptions should be reviewed regularly – usually monthly – and patients must be made aware of the risks of long-term benzodiazepine use, and doctors must document this communication. All patients with dependency should be encouraged to discontinue the drug and a detoxification programme offered to them at regular intervals.

These drugs should normally not be prescribed for periods greater than two weeks

GPs must seek specialist advice before prescribing to patients who have become dependent as a result of substance abuse. In many practices, there remains a cohort of older people who require regular prescriptions for sleeping tablets because they are now “hooked” on them.

An unknown quantity

According to Professor Colin Bradley, professor of general practice at University College Cork, GPs are aware of the dangers of the drugs, but may not be quite aware of the prevalence of the problems they cause. Speaking ahead of last year’s “Benzodiazepines: An Integrated Response” conference, Prof Bradley told Irish Medical Times the low level of risk perception was perpetuated because some GPs had some patients on benzodiazepines for some time without it seemingly doing them any great harm. It was also difficult for GPs to identify the minority for whom the drug might be doing harm, he said.

A member of the Commission on Benzodiazepine Prescribing that produced guidelines for GPs in 2001, Prof Bradley notes some 10% of GMS patients were on benzodiazepines in 2001, and ten years on this figure is largely unchanged.

GPs must seek specialist advice before prescribing to patients who have become dependent as a result of substance abuse

While this could be interpreted as a failure to implement the guidelines in general practice, it could also be due to the paucity of support services in the form of clinical psychology and cognitive behavioural therapy. But it must also be acknowledged that the simple act of writing to patients on long-term benzodiazepines, inviting them to participate in a withdrawal programme, leads to up to 10% of patients successfully coming off the drug.

Studies by the Health Research Board using the National Drug Treatment Reporting System and the National Drugs Related Deaths Index indicate a rising incidence of problems related to benzodiazepine use. And with most prescriptions for hypnotics and anxiolytics being written in primary care, GPs have a big responsibility to modify their prescribing.

A growing problem

Specialist drug treatment services are also experiencing a rise in the number of cases involving sedatives and tranquillisers. From 2003-2008 the annual number of treated cases reporting a benzodiazepine as a problem substance increased by just over 63%, rising from 1,054 in 2003 to 1,719 in 2008.

Benzodiazepines were also implicated in nearly one third (31%) of all deaths by poisoning between 1998 and 2007. Far from their origins as mother’s little helpers, benzodiazepines have shown their substance abuse potential in the last 40 years. And unless handled carefully and responsibly by doctors, benzodiazepines can not only harm patients but also damage doctors’ professional reputations to boot.