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Key reviewer: Dr Geoff Robinson, Chief Medical Officer, Capital and Coast DHB

For further information on managing misuse of prescription medicines see: Unintentional misuse of prescription medicines bpacnz, October 2018

The misuse of prescription drugs is an escalating problem in New Zealand

Key concepts
  • Drug seekers are becoming more common in general practice. The most sought after drugs are opioids and benzodiazepines.
  • Identifying a drug seeker is sometimes difficult. GPs should routinely screen any patient who is prescribed a controlled drug.
  • It is important not to withhold appropriate treatment when a drug seeker has a genuine need for pain relief. Strategies such as frequent dispensing, tamper-proof prescriptions and forming a contract can be useful to reduce risk for both doctor and patient.

The fear of being fooled by a drug seeker leaves many doctors feeling uncomfortable about prescribing controlled drugs. As a result, pain is often undertreated and patients who are refused treatment for legitimate illnesses can end up feeling stigmatised.1, 2

Which prescription drugs are commonly misused?

Benzodiazepines and opioids are the most commonly misused prescription drugs.

Benzodiazepine misuse frequently occurs when multiple drugs are misused, with the highest correlation between concurrent addiction to opioids and alcohol. Benzodiazepines are used to enhance the euphoriant effects of opioids, enhance cocaine highs and increase the effects of alcohol. They are also used to alleviate withdrawal effects from other drugs.2

Drug use in New Zealand

While the exact magnitude of prescription drug misuse in New Zealand is unknown, the Illicit Drug Monitoring System (IDMS) report conducted annually by researchers from Massey University provides some insight into patterns of drug use.3

Opioid abuse is common in New Zealand. As the supply of imported heroin is limited, the three main sources are morphine sulphate tablets, “homebake heroin” made from codeine based tablets and opium extracted from opium poppies.3

The 2007 IDMS report showed that accessing opioids is very easy. They are mainly sourced from diverted prescriptions for morphine and methadone. The average street price for opioids in New Zealand is $1 per milligram.3

Among surveyed injecting drug users, 72% used methadone, 71% used other opioids, 54% used benzodiazepines and 42% used methylphenidate. The misuse of ketamine was also reported. The frequency of use of methadone and methylphenidate is increasing.3

Stimulants may be taken to prevent fatigue (e.g. shift workers) or for their euphoric effects. Anticholinergics are taken for their hallucinogenic effects.4

Prescription drugs most commonly misused in New Zealand:5, 6

  • Amphetamines e.g. dexamphetamine
  • Anticholinergics e.g. procyclidine, benztropine
  • Benzodiazepines e.g. clonazepam, diazepam
  • Dextropropoxyphene
  • Pseudoephedrine (also sourced directly from pharmacies)
  • Ketamine
  • Methylphenidate
  • Opioids e.g. morphine, methadone, codeine, tramadol
  • Zopiclone

Most prescription drugs that are misused trigger dopamine release in the “reward pathway”. They are all also habit forming and cause a state of physiological dependence if they are taken in large enough quantities for long enough periods of time.2

Identifying drug seekers is not always simple

Recognising signs of drug-seeking and misuse

Many GPs believe they can easily identify drug seekers, but they will not all fit the expected stereotype.

Drug seekers may be known patients or casual attendees to the practice. They may be dependent on the drug or sourcing the drug for black market sale. Drug seekers are not necessarily drug abusers or drug addicts. Anyone regardless of gender, income, ethnicity, health or employment status can be a drug seeker.

In addition, not all drug seekers are faking symptoms. They may have a legitimate complaint and over time have become dependent or tolerant and require larger doses to function in their daily life.1 Patients with chronic pain, anxiety disorders and attention-deficit disorder are at increased risk of addiction co-morbidity.2

Some indicators of drug seeking behaviour are:1, 2

  • Presenting near closing time without an appointment.
  • Reporting a recent move into the area, making validation with a previous practitioner difficult.
  • Requesting a specific drug and refusing all other suggestions - the patient may claim that other medications don’t work, they have an allergy to them, a high tolerance to drugs or report losing prescriptions.
  • Inconsistent symptoms that do not match objective evidence or physical examination.
  • Manipulating behaviour which may include comparing one doctor’s treatment opinions against another’s, offering bribes or making threats.
  • Use of multiple doctors.
  • Assertive personality, often demanding immediate action.
  • Unusual knowledge of medications and symptoms or evasive and vague answers to history questions.
  • Reluctance to provide personal information such as address or name of regular doctor.
  • Signs and symptoms of intoxication or withdrawal (see below).

Many drug seekers will target doctors who are new to a practice or doctors who are sympathetic and dislike confrontation. A usual patient/doctor relationship is based on mutual respect, however a drug seeker has a stronger relationship with the prescription than with the doctor. Some doctors who are pressured for time would rather “write than fight”.2

Indicators of drug misuse

  Signs and symptoms of intoxication Signs and symptoms of withdrawal
Benzodiazepines Sedation, poor co-ordination and balance, impaired memory and general impairment of cognitive function. Anxiety, irritability, palpitations, tremor.
Opioids Constricted pupils, itching nose and skin, difficulty concentrating and dry mouth. Injection site marks may be evident. Dilated pupils, increased heart rate and blood pressure, diarrhoea, muscle cramps, aches and pains, frequent yawning, rhinorrhoea and lacrimation.

A consistent approach to managing drug seekers is best practice


Tolerance is when the dose or frequency of a drug needs to be continually increased to achieve the same level of pain control.1

Dependence is a physiological adaptation to a drug. It is dose, time and potency-related. Abrupt cessation, rapid dose reduction, decreased blood level of the drug or administration of an antagonist results in withdrawal syndrome.1, 2

Addiction involves the loss of control and an obsessive-compulsive pattern that becomes a primary illness. It may result from genetic, psychosocial and environmental factors. Physiological changes leading to tolerance or withdrawal may occur along with cognitive or psychological complications.1, 2

Drug seeking behaviour is defined as the false reporting of symptoms to obtain a prescription or requesting a drug in order to maintain dependence.4

Misuse includes using the medication in larger amounts, at a greater frequency, for different indications or by different routes than prescribed, usually resulting in adverse consequences.2

As anyone can be a drug seeker, and drug seekers are difficult to identify, a recommended strategy is to screen all patients who are prescribed controlled drugs. Ask about previous drug use, alcohol use and family history of addiction.

Managing drug-seeking behaviour

In New Zealand it is illegal to prescribe a controlled drug solely to maintain someone’s dependence, unless the prescriber is licensed to do so (e.g. drug clinics).

Practices should develop a plan for dealing with drug seekers, which is consistently adopted by all staff in the practice, at all times. This discourages drug seekers from preying on sympathetic or new staff members.

Planned responses to situations in which a doctor feels pressured to prescribe may include: 2, 4

  • Outright refusal to prescribe
  • Prescribing for a limited time (e.g. two to three days)
  • Supervised daily dosing
  • Prescribing a drug appropriate for the reported symptoms but different from the one requested by the patient
  • Seeking a second opinion from a colleague

It is important not to deny appropriate treatment

The prescription of controlled substances should be avoided in patients with current or past addictions, however they should not be withheld if warranted for acute pain.

If these medicines are prescribed, this should be done on a strict regimen rather than on an as needed basis.2 Frequent dispensing should occur (prescribe as “close control”). A larger than usual dose may be required due to tolerance to effects and the duration of treatment needs to be clearly established.4 Some doctors may consider forming a written contract with the patient.

Alternatives to controlled substances for pain relief in people with addiction to prescription drugs may include: 2

  • NSAIDs
  • Paracetamol
  • Antidepressants
  • Anticonvulsants (but not clonazepam)
  • Steroids
  • Muscle relaxants

Alternatives to medications should also be discussed including relaxation techniques, physiotherapy or psychological therapy.2

Prescribing controlled drugs for any patient requires caution

As a routine aspect of taking a new patient history or performing a general health check, ask patients about their substance-use history, including alcohol, illicit drugs and prescription drugs.2

Before prescribing a controlled drug consider whether the use is appropriate.

Managing the risk of prescribing controlled drugs5
Knowledge – review the pharmacology of controlled substances, drug interactions and signs of intoxication or withdrawal. Become familiar with alcohol and drug addiction screening assessments.

Documentation - this is essential, note the diagnosis, indications, expected symptom end points and the treatment time course. A medication flow chart may be useful to monitor refills, symptoms and prescribing.

Tamper proof prescriptions – prescribe the exact amount to carry through to the next appointment, write out the number dispensed in words not numerals, consider implementing a one doctor/one pharmacy treatment plan with the patient where only one doctor in the practice prescribes to them and prescriptions are only phoned through to one pharmacy.

Don’t be hesitant to refer to peers, supervisors or those with specialised expertise such as addiction specialists, pain management clinics or psychiatrists.2

Misuse of Drugs Act 1975 and Medicines Act 1981

These Acts allow the Medical Officer of Health to publish statements relating to a person who is, or is likely to become dependent, on any prescription medicine or restricted medicine. The statements are made available to health professionals. The purpose of the statement is to prevent or restrict the supply of medicines to that person, require its supply from only a named source or to assist in the cure, mitigation or avoidance of dependence.

The Misuse of Drugs Act also classifies drugs according to the level of harm they pose. Class A is very high risk e.g. cocaine, heroin and methamphetamine. Class B is high risk e.g. methadone, morphine and pethidine. Class C is moderate risk e.g. codeine and diazepam.

Doctors may not treat a drug dependent person with controlled drugs unless they have ministerial authority to do so. That means that doctors are unable to prescribe drugs such as opioids and benzodiazepines to a person they know, or have reason to suspect, is dependent on prescription or illicit drugs, for the purpose of maintaining or managing their addiction. The exception to this is doctors who are authorised to prescribe methadone.

For practices that keep Class B drugs on site, they must be kept in a safe and it is good medical practice to keep a drug register.7

How to seek help in dealing with prescription drug misuse

One strategy I use for suspected drug seekers is to ask them to show me some identification. Most bona fide patients will have a driving licence, or some kind of card with their name written on it. Almost never will the drug seeker have identification they are prepared to show you, in which case it is easy to say you’re sorry you can’t prescribe for them. Should they produce some positive identification, then that is useful if they need to be reported to the police or medicines control office. Christchurch GP

Early consultation with a Medicines Control Advisor is recommended if a doctor is in any doubt about the legitimacy for a request from a drug seeker. The activities of a Medicines Control Advisor include:

  • Liaising with alcohol and drug treatment centres and with doctors and pharmacists in relation to drug misuse issues
  • Advising health professionals of current drug misuse issues
  • Monitoring controlled drug prescribing
  • Working with national Medical Officers of Health in the preparation of restriction notices for drug seekers
  • Providing advice on the requirements of the Misuse of Drugs Act and Medicines Act
  • Issuing controlled drug prescription pads to prescribers.

Contact: Central Medicines Control Office, Wellington:
Tel: 04 4962437 or 0800 163 060


  1. Friese G, Wojciehoski R, Friese A. Drug seekers: do you recognise the signs? Emerg Med Serv 2005;34(10):64-7.
  2. Longo L, Parran T, Johnson B, Kinsey W. Addiction: Part II. Identification and management of the drug-seeking patient. Am Fam Physician 2000;61(8):2401-8.
  3. Wilkins C, Gurling M, Sweetsur P. Recent trends in illegal drug use in New Zealand, 2005 - 2007. Auckland: Centre for Social and Health Outcomes Research and Evaluation, Massey University, 2008. Available from (Accessed August 2008).
  4. White J, Taverner D. Drug-seeking behaviour. Aust Prescr 1997;20:68-70.
  5. McCormick R. Treating drug addiction in general practice. NZ Fam Pract 2000;27(4).
  6. Ministry of Health. National drug policy 2007 - 2012. Wellington, 2007.
  7. Chapman M. Cole’s Medical Practice in New Zealand. Chapter 3: How medical practice standards are set by legislation: Other legislation: Medical Council of New Zealand, 2008.