Drug Driving

Drug Driving

How Effective?

  • The countermeasures against drug driving and riding consist of a range of legislative measures, enforcement, education and media campaigns. The role of healthcare professionals is also vital in managing the risk of drivers and riders impaired by medicines.

The evidence determining the effectiveness of interventions targeting drug driving is weak. Therefore many of the countermeasures against drug driving are only outlined in this section. A number of large scale European drug driving projects have identified a range of countermeasures based on formal theory.

  • The majority of measures against driving under the influence are aimed at alcohol consumption and only limited measures against use of drugs and medicines whilst driving.

(SWOV, 2011)

Drug driving legislation

  • The Department for Transport ran a consultation from the 9th July 2013 to 17th September 2013 seeking feedback on proposals for drug driving limits to be specified in regulations. The government’s preferred policy option is to make it an offence to drive if any of the 16 controlled drugs are found in blood over a specific limit. A zero tolerance approach has also been proposed for 8 drugs most associated with illegal use. Analysis is currently being undertaken on the feedback and the outcome will be published shortly.

(Department for Transport, 2013)


The main enforcement method associated with drug driving is the detection and testing of drivers impaired by drugs.

  • Increasing drug enforcement is cost-effective for countries that have low enforcement levels, but is not beneficial when the increase is financed at the cost of drink-driving enforcement.

(Schulze et al. 2012)

Field Impairment Test

  • In Great Britain, police may use the Field Impairment Test (FIT) to detect whether a driver is suspected of being unfit to drive due to drug use. This is based on an observation of impairment, instead of a biological test.

  • There is a lack of data on the implementation of the FIT across police forces, therefore making it difficult to conclude the effectiveness of the FIT tool to help judgement of drug drivers.

  • Department for Transport records show that approximately 200 police constables have been approved as FIT instructors since 2005. There are no records to show whether refresher training has been undertaken.

  • The number of police constables trained to actually administer FITs is not known due to a lack of requirement for the data. Therefore there is a lack of evidence about who is trained to administer FITs, who is actively using FITs and the number of FITs administered.

  • Limited evidence is available from a 2009 Christmas drink-drive campaign (data between 1st December 2009 and 1st January 2010) on the use of FIT tests from the Association of Chief Police Officers statistics submitted to the North review. In 2009, 489 FITs were conducted compared with 481 in 2008. 87 (18%) resulted in an arrest on suspicion of drug driving. During the same time period in 2009 223,423 breath tests were administered for drink driving. However only 7600 (4%) resulted in an arrest. These data are not representative of normal policing activities. It is useful to compare the amount of FITs and breath tests conducted that result in an arrest.

(Jackson & Hilditch, 2010)

  • An evaluation by the University of Glasgow of the FITs conducted between 2001 and 2003 concluded that the FIT is an effective screening tool, but further development would be beneficial to improve specificity and predictive value of all the tests.

(Oliver et al., 2006)


  • In England and Wales police forces submit blood samples for analysis to a laboratory that is approved under the police National Procurement Framework.

  • If a FIT is undertaken, the police procedures specify that any sample taken is sent with the appropriate forms (Manual of guidance drink and drug driving) with details of the observations from the FIT.

(Home Office, 2013)

  • If additional information is not supplied to the laboratories then they apply a standard panel of drug tests to attempt to find common misused drugs.

  • The prosecution of drivers with positive blood tests is provided by the Ministry of Justice. In 2007 for drugs there were 646 proceedings with 412 findings of guilt (63.8%). This figure is much lower for proceedings in 2008 (253) and 168 findings of guilt. When compared to proceedings for drink driving offences, drug-related offence proceedings represent about 1% of drink driving offence proceedings.

(The North Report, 2010)

Roadside drug testing update

  • “The Railways and Transport Safety Act 2003 gave British police the power to require a driver suspected of being unfit to drive because of drugs to undertake a preliminary drug test” (p.40)

(Jackson & Hilditch, 2010)

  • The DRUID project tested the practicality of available oral fluid drug screening devices with police officers. The results showed that the majority of systems investigated were not effective when taking into account specificity and sensitivity. Therefore the detection of drugs may be influenced by the device used. It is also noted that large-scale random drug testing is expensive and requires the collection and analysis of samples. From the 13 devices investigated, eight were rated as ‘promising’.

(Schulze et al., 2012)

  • The Home Office has recently type approved a station screening device.

(UK Government, 2013)

Setting limits

  • The recent consultation of drug driving law by the Government proposed several options. Option 1 is preferred by Government and includes a zero tolerance approach to eight controlled drugs that impair driving (e.g. cannabis). Option 2 details limits for 15 controlled drugs following an expert panel’s recommendation. Option 3 proposes a zero tolerance approach for 16 controlled drugs. The results from the consultation are awaiting publication.

(Department for Transport, 2013)

  • Zero tolerance laws have been found to be unsuccessful at deterring offenders driving under the influence of drugs. However, in Sweden, following the introduction of zero tolerance laws over 1ten years ago, the cases of driving under the influence of drugs and successful prosecutions have increased.

  • It is difficult to determine values that represent impairment in the general population due to the complex nature of drugs. The zero tolerance approach overcomes difficulties proving impairments and deciding cut-off levels, but may have the potential to penalise drivers who are not impaired and pose no risk to safety.

(Jackson & Hilditch, 2010)


The Department for Transport THINK! campaign on drug driving aimed to:

  • Increase awareness of drug driving and clarify the misconceptions around the law and the effects of drugs on driving ability.

  • Support and amplify awareness of enforcement campaigns and local stakeholders’ activities.

  • Raise awareness of the potential effectives of medicine on driving ability whilst reminding consumers to take their medication as instructed.

(Department for Transport, 2009)

An evaluation was undertaken using a qualitative approach investigating campaign awareness and communication, attitudes towards drug driving and perceived consequences of drug driving. However, the campaign did not determine the extent of drug driving pre- and post-campaign. The campaign included TV, press, online and poster advertising. Data were collected in July and September 2009, with the campaign being launched in August 2009.

Campaign awareness:

  • 71% of respondents had heard or seen the advertising or publicity. For the target group (17-34 year olds) awareness of the campaign was 76%.

  • The target group under the age of 35 (76%) and men (75%) were significantly more likely to be aware of the campaign overall.

Campaign Communication:

  • The TV advertising had the highest impact with 40% respondents stating that it stuck in their mind.

  • 38% said they realised as a consequence of the advert that drug driving had the same penalty as drink driving.

Attitudes towards recreational drugs and driving:

  • A higher percentage of respondents felt that the issue of drug driving was being taken seriously by the government following the campaign (47% pre-campaign, 64% post-campaign).

Likelihood of being stopped by police and detected for drug driving:

  • There was no significant change in the perception of being caught drug driving following the campaign.

  • 76% perceived that it would be ‘easy’ for the police to tell if a driver was impaired by drugs, and 28% ‘very easy’.

Consequences of drug driving:

  • 69% of respondents felt a driver was likely to be convicted if caught drug driving.

  • The greatest worry for being convicted of drug driving is being given up to 6 months imprisonment and a criminal record.

(Angle et al., 2009)

International evidence

The European project DRUID identified a number of countermeasures to address both driving under the influence of illicit drugs and driving while impaired by medicines, based on empirical research evidence generated in the project.

Driving under the influence of illicit drugs:

  • Target groups (young male drivers; drivers with combined consumption of illicit drugs and alcohol).

  • Legal regulations (European agreement regarding the body fluid to be used for drug detection; regulations should be based on scientific findings; European harmonisation of drug analyses).

  • Enforcement strategies (increased of drug enforcement cost-beneficial for countries with low enforcement, but not at the cost of drink driving enforcement; use of screening devices which fulfil practical and scientific requirements is advised; training of police officers to improve drug detection required; drug detection at the roadside should be targeted).

  • Rehabilitation measures (driver rehabilitation) should be standardised, legally regulated and based on a defined criteria; drug offenders should be treated in different groups to alcohol offenders; non-addicts and addicts should be identified as they will require different interventions).

  • Withdrawal measures (should be combined with adequate rehabilitation programs).

Driving impaired by medicines:

  • Target groups (healthcare providers and patients; female drivers above 50 years – especially those using benzodiazepines and medicinal opiates).

  • Legal regulations (no thresholds should be defined for medicines; information about possible side effects and how to decide to use the medicines in a safe manner while driving are an adequate countermeasure; implementation of the four level classification).

  • Enforcement strategies (only appropriate for misuse by patients or healthy drivers; focus should be on combined consumption of medicines and alcohol).

  • Rehabilitation measures (misuse same as recommendations for illicit drugs).

  • Withdrawal measure (misuse and combined consumption with alcohol same as illicit drugs).

(Schulze et al., 2012)

The IMMORTAL project also provided some conclusions and recommendations based on research undertaken to support EU Policy on licensing and roadside testing:

  • Drug recognition methods still need to be improved and saliva test devices tend to be error-prone.

  • Due to the increase in the combination of alcohol and drugs, and combined use of different drugs it is important that the impairment of alcohol and drugs is recorded.

  • Good screening instruments for the impairment of drugs need to be used alongside random breath test devices.

  • Licensing needs to maintain consistent standards and be reliable.

  • Interventions should target specific groups of drug users.

  • Rehabilitation programmes for various conditions should be implemented by adopting best practice models throughout the EU.

  • Healthcare professionals need to be informed about the effects of medicines on driving performance and communicate this information to patients.

  • Zero tolerance legislation (with the exception of Heroin) aimed at single use of illegal drugs seems to lead to high costs and minimal road safety benefits.

(Klemenjak et al., 2005)

The USA has a goal of reducing the amount of drug driving by 10% in 2015 as detailed in The National Drug Control Strategy. To achieve this goal the strategy outlines the following areas:

  • States to adopt a Per Se (someone is guilty of driving under the influence if they test positive for a certain level and no additional proof of impairment is necessary to obtain a conviction) drug impairment law.

  • Collection of further data on drug driving.

  • Enhancing prevention of drug driving by educating communities and professionals.

  • Provision of increased training to law enforcement on identifying drug drivers.

  • Development of standard screening methodologies for drug-testing laboratories to detect the presence of drugs.

(USA Government, 2013)

The main countermeasures for drug impaired driving identified by the international evidence include targeting specific groups, drug detection at the roadside, rehabilitation programmes and the role of healthcare professionals in communicating the effects of medicines on driving performance.

The role of the healthcare professionals

The impairing effects on driving may be similar for illicit and medicinal drugs, however there are significant differences in how to intervene. Medicinal drugs have the potential for healthcare professionals to manage the risks medicines may cause.

  • Healthcare professional advice provided to patients, medical categorisation and labelling of medicines by the pharmaceutical industry all have a role in reducing the risk of medicines impairing drivers.

(The North Report, 2010)

  • Effective communication provided by physicians and pharmacists about the potential dangers of combining driving and riding with medicines that impair driving and riding skill could contribute to a reduction in the number of casualties.

(SWOV, 2011)

Healthcare professionals’ advice

  • A study identified the attitudes of health professionals advising patients about their fitness to drive as set out by the DVLA (Driver Vehicle Licensing Agency) medical standards. Various methods were used including surveys, questionnaires, interviews, focus groups and workshops.

  • The findings suggested doctors receive little tuition on medical aspects of fitness to drive and knowledge is derived from specialist clinical training, post-graduate courses and clinical placements. Other healthcare professionals received no formal training on fitness to drive. The majority of health professionals were aware of the guidelines provided by the DVLA, had consulted with them in the past two years and advised at least one patient to stop driving in the previous three months. However, the majority of healthcare professionals were unable to reliably determine those medically unfit drivers, borderline drivers and fit drivers. 91% of patients interviewed felt it was the healthcare professionals that should advise them on medical conditions that may affect fitness to drive. The focus of this study was on medical conditions; however it is not unreasonable to suggest that healthcare professionals may not be advising patients fully on the impairing effects of some medicines.

(Hawley et al., 2010)

Medical categorisation

  • Following the review of the most significant categorisation systems in Europe the DRUID project proposed a four-level classification and labelling system for medicines regarding their influence on driving performance. The categories were a) no or negligible influence, b) minor influence, c) moderate influence, and d) major influence on fitness to drive

(Schulze et al., 2012)

Labelling of medicines

  • Wording for prescribed medicines is recommended by the British National Formulary for cautionary and advisory labels. Pharmacists are recommended to use one of three labels providing a warning about drowsiness on a number of medicines. Medicines for use by adults should also advise against driving or using machinery if drowsiness is a symptom.

  • Over-the-counter medicines tend to be labelled by the manufacturer.

  • There is a statutory requirement (since 1994) on warning for drowsiness when using antihistamines and the need for caution if driving or using machinery. However, a review of over one hundred over the counter medicines with the potential to cause drowsiness showed that there were inconsistencies in accuracy of the information of drowsiness and dosage (Barrett & Horne, 2001). It was recommended that Great Britain should introduce a standard symbol warning of drowsiness.

(The North Report, 2010)

Gaps in the evidence

Despite the growing concern for drug driving and riding in Great Britain there are a number of gaps in the evidence. The key areas include:

  • The current prevalence of drug driving/riding and recent trends in drug use.

  • The current prevalence of drug driving and riding as a contributory factor to road users involved in accidents and fatalities.

  • The attitudes, behaviours and motivations towards drug driving and riding.

  • The specific target groups to focus countermeasures on to deter drug driving and riding.

  • The effectiveness of countermeasures against drug driving, specifically legislation, enforcement and campaigns.

  • The effectiveness of the Field Impairment Test and extent to which it is being used by police forces across Great Britain.


  • Date Added: 03 Apr 2012, 08:10 AM
  • Last Update: 26 Jan 2017, 04:07 PM