England 2015/16 to 2021/22

Published 8 September 2022

Last reviewed and updated 8 September 2022

Key findings

  • In 2021/22, there were 67.7 million items for dependency forming medicines prescribed in England a 0.13% decrease from 2015/16.

  • In 2021/22, the cost of dependency forming medicines prescribed in England was £405 million. This was a 48.0% decrease from 2015/16 where the cost was £779 million.

  • Opioid drugs were the most prescribed dependency forming medications in England in 2021/22 with 39.6 million items at a cost of £307 million. The total cost of opioid drugs has decreased by 26.7% since 2015/16 from £419 million.

  • There were 7.10 million identified patients that were prescribed dependency forming medications in England in 2021/22. This was a 1.16% increase from 7.02 million identified patients in 2020/21, and an 11.8% decrease from 8.05 million in 2015/16.

  • The most common group to receive prescribing for dependency forming medications in 2021/22 was female patients aged 55 to 59 with 406,000 identified patients. The next most common groups were female patients aged 70 to 74 and female patients 60 to 64 .

  • Areas of greater deprivation had the highest number of identified patients who were being prescribed dependency forming medication in 2021/22, with one and a half times as many patients receiving prescribing in the most deprived areas of the country compared to the least deprived.


1. Introduction

1.1. Scope

This release is the first in a new publication series by the NHSBSA. This publication has been developed in response to the Public Health England (PHE) dependence and withdrawal associated with some prescribed medicines review also known as the prescribed medicines review (PMR), particularly its recommendation that the availability and use of data on the prescribing of medicines that can cause dependence be increased.

This publication includes data on 5 classes of medicines overall:

  • Antidepressants
  • Opioid pain medicine
  • Gabapentinoids
  • Benzodiazepines
  • ‘Z’ drugs

Antidepressants are not included in the volume and cost or demographics measures. The current National Institute for Health and Care Excellence (NICE) guidance makes the distinction that antidepressants can cause withdrawal symptoms but are historically not dependency forming. Additionally, the statistics for antidepressants can be found in the Medicines Used in Mental Health publication. Antidepressants are included in the co-prescribing measures in this publication.

This publication aims to describe the prescribing of dependency forming medications in England that are dispensed in the community. This does not include data on medicines prescribed and dispensed in secondary care, prisons, or issued by a private prescriber as this is not held by the NHSBSA.

These statistics detail:

  • the total number of prescription items issued for dependency forming medication
  • the total cost of prescription items issued for these drugs
  • the number of identified patients that have received prescribing for these drugs
  • the number of identified patients receiving more than one dependency forming medication
  • demographic breakdowns of prescribing by age group and sex
  • demographic breakdowns by sex
  • demographic breakdowns by a measure of deprivation.

These statistics use the BNF therapeutic classifications defined in the British National Formulary (BNF) using the classification system prior to BNF edition 70. Each January the NHSBSA updates the classification of drugs within the BNF hierarchy which may involve some drugs changing classification between years of this publication. The categories of dependency forming drugs do not align to specific sections of the BNF and have been filtered on chemical substance. A complete list can be found in appendix A of the background and methodology note that accompany this release.

Many drugs have multiple uses, and although classified in the BNF by their primary therapeutic use may be issued to treat a condition outside of this. Due to this, these statistics may not give accurate estimations of prescribing to treat specific conditions. This also means that unlike the PMR which excluded opioids prescribed for cancer, using patient details from the PHE cancer registry, these statistics do not exclude patients diagnosed with cancer and who are using an opioid to manage the pain that can be associated with malignant diseases, especially as part of end-of-life care. This means that some measures and the data for opioid pain medicines include more patients than the PMR analysis.

To exclude items used to treat an existing drug dependence or substance misuse disorder, drugs prescribed on FP10MDA installment forms and from BNF Section 0410 — Drugs used in substance dependence were excluded from these statistics.

1.2. Key events

Date Event
June
2015
All Party Parliamentary Group for Prescribed Drug Dependence launched to address the growing problem of prescribed drug dependence.
September 2019 Public Health England (PHE) prescribed medicines review (PMR) intended to identify the scale, distribution and causes of prescription drug dependence published.
August 2021 Updated Opioid medicines and the risk of addiction Safety leaflet published by Medicines and Healthcare products Regulatory Agency (MHRA)
April 2022 Medicines associated with dependence or withdrawal symptoms: safe prescribing and withdrawal management for adults guidance published by National Institute for Health and Care Excellence (NICE)
May
2022
Opioid comparator dashboard to support Primary Care Networks (PCN) and GP practices published by NHSBSA

1.3. Definitions

The medicines included in these statistics are those that can cause issues with dependence. Dependence is an adaptation to repeated exposure to some drugs and medicines usually characterised by tolerance and withdrawal, though tolerance may not occur with some.

Tolerance is a neuroadaptation arising from repeatedly taking some drugs and medicines, which can mean higher doses are required to achieve the same effect. Withdrawal is the side effects or physiological reactions that a patient experiences when they stop taking a medication.

Addiction is the combination of dependence plus compulsive behaviours including patients not having control over doing, taking or using something to the point where it could be harmful to them.

Throughout this publication the term ‘item’, short for ‘prescription item’, means a single instance of a drug that is listed as a separate entry on a prescription form. For example, Fluoxetine 20mg tables x56.

There are many costs incurred when a dispensing contractor fulfils a prescription. The costs reported in this publication represent the basic price of the item and the quantity prescribed. This is sometimes called the ‘Net Ingredient Cost’ (NIC). The basic price is given either in the Drug Tariff or is determined from prices published by manufacturers, wholesalers or suppliers. Basic price is set out in Parts VIII and IX of the Drug Tariff. For any drugs not in Part VIII, the price is usually taken from the manufacturer, wholesaler or supplier of the product.

In this release the term ‘patient/s’ is used to mean a unique, valid NHS number that has been captured from a prescription form and subsequently verified by the NHS Personal Demographics Service (PDS). Across 2021/22, use of the Electronic Prescription Service (EPS) has increased considerably during the COVID-19 pandemic. As this process captures NHS numbers digitally rather than through scanned paper forms, this has naturally led to an increase in the proportions of identified patients in 2021/22 than seen in previous years.

Where patients are identified, their age is calculated on 30 September of the given financial year to assign them to a single age band. For patients where date of birth has not been captured, they have been included in a category of unknown.

Sex information was not available from PDS for a number of patients in each year, typically less than 0.01%. This may be because it was not disclosed by the patient or not recorded by the organisation that collected the data.

The English Indices of Deprivation 2019 have been used to provide a measure of patient deprivation. This provides an Index of Multiple Deprivation (IMD) looking at different factors such as income, employment and health deprivation and ranks areas of England in deciles based on their score, where 1 is the most deprived and 10 the least deprived. For our publication, the IMD is derived from the address of the patient.

1.4. Patient identification

When the NHSBSA processes prescriptions, the NHS number of the patient is identified for most, but not all, prescriptions. The proportion of items for which a patient could be identified is shown in Table 1. This means that data relating to patient counts represents most, but not all, patients.

These statistics do not contain any personally identifiable data. More details on the statistical disclosure control applied to these statistics is available in section 5 of this summary. More information about how the NHSBSA protects personal information can be found in the statement on confidentiality and access.

Where data is provided “per patient”, this refers to only costs or items attributable to identified patients. Therefore, these will not total overall costs or items which refer to all known costs or items.

Table 1: The proportion of items for which an NHS number was recorded for listed Drug Categories 2017/18 to 2021/22

Source: Dependency forming medicines summary tables - Costs and items (Patient identification rates)


2. Results and commentary

2.1. Volume and cost

Figure 1: Number of dependency forming medicine items and patients prescribed per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 1)

There were 67.7 million items for drugs classed as dependency forming prescribed in 2021/22. This was a 0.13% decrease from 2015/16, and a 0.04% decrease from 2020/21. The number of items of dependency forming medicines has been decreasing since 2016/17.

The number of identified patients that received prescribing for a dependency forming medication was 7.10 million in 2021/22. This was an 11.8% decrease from 8.05 million identified patients in 2015/16, and a 1.16% increase from 7.02 million in 2020/21. The increase in identified patients between 2020/21 and 2021/22 was the first increase following decreases for the 4 previous years.

Figure 2: Cost of dependency forming medicines per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 1)

Costs for dependency forming medications also decreased to £405 million in 2021/22. This was a 48.0% decrease from £779 million in 2015/16, and a 3.43% decrease from £419 million in 2020/21. The total cost saw a large decrease of over 26% from 2016/17 to 2017/18 and 2017/8 to 2018/19 but has seen smaller fluctuations between 2019/20 and 2021/22.

The changes from 2016/17 to 2018/19 were due to Pregabalin, a gabapenintoid coming off patent and entering Category M of the drug tariff, meaning cheaper generic equivalents could be prescribed from August 2017 which can be seen more clearly in figure 5.

Figure 3: Number of dependency forming medicine items prescribed by Drug Category per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 2)

Opioid drugs remain the most prescribed dependency forming medicine with 39.6 million items in 2021/22. This was a 5.07% decrease from 41.8 million items in 2015/16, and a 0.11% decrease from 39.7 million items in 2020/21. The number of opioid items prescribed has decreased every year since 2016/17.

Prescribing of gabapenintoids increased by 3.32% from 15.3 million items in 2020/21 to 15.8 million in 2021/22, while the two remaining Drug categories observed decreases in prescribing between 2020/21 and 2021/22. Benzodiazepine items decreased by 4.03% from 7.05 million to 6.77 million. Finally, Z-drugs decreased by 3.68% from 5.68 million items in 2020/21 to 5.47 million in 2021/22.

Figure 4: Number of identified patients per 1000 population by drug category per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 5)

There were 99 patients per 1000 population receiving opioid drugs, approximately 9.9% of the population of England in 2021/22, an increase of 1.2 patients per 1000 population from the 98 per 1000 population in 2020/21. This was the first increase after five years of consecutive decreases from 117 patients per 1000 population in 2015/16.

Both benzodiazepines and Z-Drugs have decreased the number of patients per 1000 population for 6 consecutive years. Benzodiazepines dropped from 19 patients per 1000 population in 2020/21 to 19 patients per 1000 population in 2021/22 (approximately 1.9% of the population of England). Z-Drugs dropped from 16 patients per 1000 population in 2020/21 to 15 patients per 1000 population in 2021/22 (approximately 1.5% of the population of England).

The patients per 1000 population receiving gabapenintoids increased in 2021/22 to 27 patients per 1000 population from 26 per 1000 patients in 2020/21 (approximately 2.6% of the population of England.) It had decreased for the two previous years.

The patients per 1000 population are calculated using the ONS population mid-year estimates, ONS population estimates for 2021/2022 were not available prior to publication so the figures for 2021 are taken from the Census which is based on the population as of 31 March 2021. Future iterations of the statistics will use the mid-year estimate where available.

Figure 5: Cost of dependency forming medicines prescribed by Drug Category per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 2)

In 2021/22, opioid drugs had a cost of £307 million. This was a decrease of 26.7% from £419 million in 2015/16, and an 4.68% decrease from £322 million in 2020/21. These decreases in cost are much greater than the respective decreases in the number of prescribed items. The cost for opioid drugs has decreased between 2020/21 and 2021/22 after increasing for the previous 2 years.

Gabapenintoids had a cost of £68.5 million in 2021/22 a decrease of 78.7% from the £322 million in 2015/16 and a 0.46% increase from the £68.2 million in 2020/21. The cost of gabapenintoids has increased for the past 2 years after decreasing in consecutive years between 2017/18 and 2019/20 following pregabalin entering category M of the drug tariff meaning cheaper generic equivalents could be prescribed from August 2017.

For the remaining two drug categories, Benzodiapezines increased in cost by 4.22% from £24.2 million in 2020/21 to £25.2 million in 2021/22 and Z-drugs decreased in cost by 13.0% from £5.19 million in 2020/21 to £4.52 million in 2021/22.

Figure 6: Average number of dependency forming medicine items per patient per financial year

Source: Dependency forming medicines summary tables - Costs and items (Table 1)

The average number of items per patient increased each year between 2015/16 and 2020/21, from 7.82 dependency forming medicine items per patient to 9.50. However, between 2020/21 and 2021/22 the average number of dependency forming medicines items per patient decreased from 9.50 items to 9.40 This was the first annual decrease in average number of items per patient.

This measure only includes prescribing of dependency forming medicines and does not include any items prescribed from other BNF sections.

2.2. Patient demographics

Figure 7: Number of identified patients receiving dependency forming medicine prescribing by sex per financial year

Source: Dependency forming medicines summary tables - Patient demographics (Table 2)

While the overall number of identified patients receiving dependency forming medicines prescribing has decreased year-on-year, the overall split of male and female patients has remained consistent. In 2015/16, 60.6% of identified patients were female and 39.4% were male. This is a similar proportion to 2021/22 where 61.3% of identified patients were female and 38.7% were male. However, there are 527,000 fewer female identified patients than there were in 2015/16, and 421,000 fewer male identified patients.

Identified patients where their sex was unknown or indeterminate have been grouped together and can be found in the summary tables that accompany this release.

Figure 8: Number of identified patients receiving dependency forming medicine prescribing by age and sex 2021/22

Source: Dependency forming medicines summary tables - Patient demographics (Table 6)

The most common group to receive prescribing for dependency forming medicines in 2021/22 was female patients aged 55 to 59 with 406,000 identified patients, 5.72% of all patients. The next most common groups were female patients aged 70 to 74 with 404,000 and 5.69% of identified patients, and female patients 60 to 64 with 397,000 and 5.59% of identified patients.

More information on how we calculate a patient’s age can be found in section 4 of this summary.

Figure 9: Number of identified patients receiving dependency forming medicines prescribing by IMD quintile 2021/22

Source: Dependency forming medicines summary tables - Patient demographics (Table 8)

In 2021/22, there were 1.80 million identified patients prescribed dependency forming medicines in the most deprived areas in England, 1.66 times more than the 1.09 million identified patients that received prescribing from in the least deprived areas. In general, more people were prescribed dependency forming medicines in more deprived areas in 2021/22. This pattern has remained consistent since 2015/16.

The English Indices of Deprivation have been used to provide a measure of patient deprivation. The deprivation quintiles reported are those of the patient. More information on this measure can be found in section 4 of this summary.

2.3. Co-prescribing of drug categories

Figure 10: Number of identified patients receiving more than one category of dependency forming medicines prescribing by number of categories March 2022

Source: Dependency forming medicines summary tables - Patient demographics (Table 10)

Co-prescribing is where a patient is receiving drugs from more than one category of dependency forming medicine. Antidepressants which have been excluded from the previous sections have been included here because of the increased risk factors when combined with dependency forming medicines. It is not possible to distinguish whether multiple prescriptions have been reported for the same month are given consecutively or concurrently. As such, some activity will show as co-prescribing when in fact the individual was prescribed one medicine and then separately the other, where both were reported in the same month. March 2022 has been used for this analysis as the most recent month and as it was representative of the recent trends in co-prescribing.

In total, an estimated 6.49 million identified patients received a prescription in March 2022 in at least one of the classes. Of these 1.61 million were receiving prescriptions in 2 or more classes, representing 24.9% of patients. Less than a tenth of a percent of patients received a drug from all 5 categories of dependency forming medication. These proportions were consistent across 2021/22.

Figure 11: Number of identified patients receiving prescribing of a combination of two dependency forming medicines in March 2022

Source: Dependency forming medicines summary tables - Patient demographics (Table 11)

The most popular combination of drugs in March 2022 for those patients receiving items from 2 categories of dependency forming medicines was opioids and antidepressants, with 633,000 (51.9%) of patients. This was followed by gabapentinoids and antidepressants with 205,000 patients (16.8%) and opioids and gabapentinoids with 150,000 patients (12.3%) These proportions were consistent across 2021/22.


3. Background

3.1. Opioid pain medicine

Opioids provide pain relief by acting on areas in the spinal cord and brain to block the transmission of pain signals.

Most opioids are schedule 2 controlled drugs (unless very low strength which may be schedule 5) and available in a wide variety of medication forms.

Opioids should only be considered for the short to medium-term treatment of chronic non-malignant pain, when other therapies have been insufficient and the benefits of use are considered to outweigh the risks of harm.

Opioid analgesics are usually used for palliative care where potential for dependence is not a deterrent and chronic (lasting more than 12 weeks) moderate-to-severe pain where other treatments have been insufficient due to the potential for dependence.

You can find out more information on opioid analgesics on the NICE website. Resources for the prescribing of opioids have been produced by the Faculty of Pain Medicine in partnership with PHE.

3.2. Gabapentinoids

Gabapentinoids is the combined name for gabapentin and pregabalin which are antiepileptic drugs also used in the treatment of neuropathic pain and in the case of pregabalin, anxiety.

In epilepsy, gabapentinoids stop seizures by reducing the abnormal electrical activity in the brain.

With nerve pain, they block pain by affecting the pain messages travelling through the brain and down the spine.

When pregabalin is used to treat anxiety it prevents the brain from releasing the chemicals that cause anxiety.

Both gabapenintoids are schedule 3 controlled drugs and are available as capsules, tablets, or a liquid.

You can find out more about gabapentin and pregabalin on the NHS website.

3.3. Benzodiazepines

Benzodiazepines are a commonly used hypnotic and anxiolytic medicine; Hypnotics and anxiolytics are used to treat insomnia and anxiety respectively. Benzodiazepines work by increasing the effects of a calming chemical in the brain called gamma-aminobutyric acid (GABA).

Benzodiazepines are indicated for the short-term relief of severe anxiety; long-term use should be avoided and should also only be used to treat insomnia only when it is severe, disabling, or causing the patient extreme distress

The majority of benzodiazepines are schedule 4 controlled drugs with some belonging to schedule 3 and are available as capsules, tablets, injectables, suppositories or a liquid.

Insomnia is difficulty getting to sleep or staying asleep for long enough to feel refreshed in the morning, despite there being enough opportunity to sleep. The most common problem with insomnia is difficult falling asleep (sleep-onset insomnia). An insomniac may also experience:

  • waking in the night
  • not feeling refreshed after sleep and not being able to function normally during the day
  • feeling irritable and tired and finding it difficult to concentrate
  • waking when they have been disturbed from sleep by pain or noise
  • waking early in the morning

Anxiety is a feeling of unease, such as worry or fear, which can be mild or severe. Everyone experiences feelings of anxiety at some point in their life and feeling anxious is sometimes perfectly normal. However, people with generalised anxiety disorder (GAD) find it hard to control their worries. Their feelings of anxiety are more constant and often affect their daily life. There are several conditions for which anxiety is the main symptom. Panic disorder, phobias and post-traumatic stress disorder can all cause severe anxiety.

You can find more information about insomnia and anxiety from the NHS website and further information about hypnotics and anxiolytics at at the NICE website though this includes drugs other than benzodiazepines.

3.4. Z-drugs

Z drugs are non-benzodiazepine hypnotics made up of zaleplon, zolpidem and zopiclone. As hypnotics they are also used to treat insomnia. Z drugs work by affecting a calming chemical in the brain called gamma-aminobutyric acid (GABA).

Zolpidem is a schedule 4 controlled drug and is available as tablets or a powder. Zaleplon is not a controlled drug and is available as a capsule and zopiclone is not a controlled drug and is available as capsules, tablets, or a liquid.

You can find more information about insomnia on the NHS website and further information about hypnotics and anxiolytics on the NICE website.

3.5. Antidepressants

Antidepressant drugs are licensed to treat major depression. Health professionals use the words depression, depressive illness or clinical depression to refer to depression. It is a serious illness and very different from the common experience of feeling unhappy or fed up for a short period of time. Depressed people may have feelings of extreme sadness that can last for a long time. These feelings are severe enough to interfere with daily life, and can last for weeks, months or years, rather than days.

It should be noted that antidepressant drugs are used for indications other than depression, for example migraine, chronic pain, Myalgic Encephalomyelitis (ME), or a range of other conditions. Clinical indication isn’t captured by the NHSBSA. Therefore, the statistics on these drugs do not relate solely to prescribing for depression.

You can find more information about depression on the NHS website.


4. About these statistics

Further information on the methodology used in this publication and further background information is available in our Background Information and Methodology supporting document.

4.1. Patient counts

The patient counts shown in these statistics should only be analysed at the level at which they are presented. Adding together any patient counts is likely to result in an overestimate of the number of patients. A person will be included, or counted, in each category or time period in which they received relevant prescriptions. For example, if a patient received a prescription item for a dependency forming medicines product in 2018/19 and another in 2019/20, then adding together those totals would count that patient twice. For the same reason, data on patient counts for different drug categories should not be added together.

4.2. Patient age and sex

The age and sex of patients used in these statistics is derived from data provided by the NHS Personal Demographics Service (PDS) for NHS numbers that have been successfully verified by them. A patient’s age, used to assign them to an age group, has been calculated on 30 September for the given financial year. It is possible that a patient’s PDS information may change over the course of the year, in these cases patients may be subject to multiple counting in these analyses.

4.3. Index of deprivation

The English Indices of Deprivation 2019 have been used to provide a measure of patient deprivation. The English Indices of Deprivation are an official national measure of deprivation that follows an established methodological framework to capture a wide range of individuals’ living conditions.

The reported IMD quintile, where 1 is the most deprived and 5 the least deprived, is derived from the lower-layer super output areas (LSOAs) of the identified patient. There are a number of items each year that we have reported as having an unknown IMD quintile. These are items that have been where we have been unable to match the patient LSOA to a LSOA postcode in the National Statistics Postcode Lookup (NSPL) - May 2022.

IMD quintiles are calculated by ranking census lower-layer super output areas (LSOAs) from most deprived to least deprived and dividing them into 5 equal groups. These range from the most deprived 20% (quintile 1) of small areas nationally to the least deprived 20% (quintile 5) of small areas nationally.

4.4. Geographies included in this publication

The patient deprivation measures given in these statistics are based upon the LSOA of the patient as matched to the May 2022 NSPL file. However, higher geographies included in the statistical summary tables of this publication, such as Integrated Care Board (ICB) use NHSBSA administrative records, not geographical boundaries, and more closely reflect the operational organisation of practices than other geographical data sources.

4.5. Co-prescribing measures

In these statistics, co-prescribing refers to the reporting of 2 or more drug categories of medicine for the same identified patient in the same month. co-prescribing is reported based on the number of categories (up to 5) that were reported in the same month, with greater than one deemed to be co-prescribing. The main limitation is that it is not possible to distinguish whether multiple prescriptions have been reported for the same month are given consecutively or concurrently. As such, some activity will be flagged in this analysis as co-prescribing (implying concurrent receipt) when in fact the individual was prescribed one medicine and then separately the other, where both were reported in the same month

4.6. Planned changes to this publication

This is an experimental official statistic release. Experimental statistics are newly developed or innovative statistics. These are published so that users and stakeholders can be involved in the assessment of their suitability and quality at an early stage. More information on how users can give us their feedback can be found in section 7 of this summary. We will regularly be reviewing the methodology used within the statistics.


5. Statistical disclosure control

Statistical disclosure control has been applied to these statistics. Patient count, items, and net ingredient cost (NIC) have been redacted in the supporting summary tables if they relate to fewer than 5 patients. Further information about our statistical disclosure control protocol can be found on our website.

The high-level figures in this statistical summary have been rounded where appropriate for clarity, in most cases to three significant figures. This is to make this narrative as accessible as possible to all readers. The summary tables released with this publication allow users to investigate this data at lower levels of granularity. Figures in the supplementary tables have not been rounded.


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7. Revisions to this publication

8 September 2022

  • Key finding for total dependency forming medicines split out into items and cost to increase user understanding based on initial feedback.

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