Proton pump inhibitors - too much of a good thing?

Published in MedicineWise News

Date published: About this date

Clinical content may change after this date. This information is not intended as a substitute for medical advice from a qualified health professional. Health professionals should rely on their own expertise and enquiries when providing medical advice or treatment.

Key messages

  • Review patients taking a PPI long term to evaluate if indication persists – daily, long-term use is only recommended in selected groups.
  • Consider risks of PPI use particularly in higher-risk groups such as older people.
  • Discuss with patients the expected initial duration of PPI therapy and plans for stepping down.
  • Consider stepping down PPI therapy in GORD patients once symptoms are well controlled.
  • Review use of concomitant medicines and advise patients about those that may exacerbate heartburn or reflux symptoms.
  • Encourage lifestyle modifications appropriate to the patient.

In 2013–14, there were over 19 million prescriptions for PPIs in Australia.1 Most prescriptions for PPIs are for managing GORD.2

Proton pump inhibitors – the good and bad

Click to expand Pathogenesis of GORD. Most episodes of gastro-oesophageal reflux are caused by transient lower oesophageal sphincter relaxation

Pathogenesis of GORD. Most episodes of gastro-oesophageal reflux are caused by transient lower oesophageal sphincter relaxation.3

Until the late 20th century, acid–peptic disorders such as gastro-oesophageal reflux disease (GORD) condemned those affected to a lifetime of ineffective dietary restrictions and antacids.4 Complications from these disorders were a persistent problem in gastroenterology,5 the only effective long-term treatment being surgery.6 The discovery of gastric-acid suppressing medicines – H2 receptor antagonists and proton pump inhibitors (PPIs) – marked a change. Although both classes of medicines provide symptom relief in GORD, PPIs are significantly more effective than Hantagonists at relieving symptoms and healing oesophagitis.7,8

While highly effective with a favourable safety profile, use of PPIs is not without concern. Since their introduction in the early 90s, PPI use has increased by more than 1000% in Australia,2 with over 19 million prescriptions in the 2013–14 financial year.1 Over the last decade, at least two PPIs have featured in the top 10 most prescribed PBS-subsidised medicines every year.1,9 Not surprisingly, there is growing international concern over their increasing use.2,10 Long-term use is only recommended in selected populations11,12 but data indicate that this accounts for most of the total use.10 Several studies suggest that a substantial proportion of PPI users do not have a clear indication for therapy (Table 1).13-18

Some reports have linked PPI use to increased risk of fractures, pneumonia, enteric infections, vitamin and mineral deficiencies, and acute interstitial nephritis.5,19 Although the absolute risk is very low, many of the patients in these reports were older people – a group that makes up the largest proportion of PPI users 2 and who are at increased risk of medicine-related problems.20 While there is insufficient evidence to establish causation, these reports deserve consideration.

There are also financial implications of overuse, with extensive costs to both individuals and government. In the 2013–14 financial year, there were close to 7 million PBS-subsidised prescriptions for esomeprazole in Australia, at a cost of over $200 million to the PBS.1

While PPIs remain a mainstay of management of acid–peptic disorders, the concerns about adverse effects and cost associated with over-prescribing highlight the need for increased attention to their judicious use.

Short-term PPI use appropriate for many acid–peptic disorders

In uncomplicated acid–peptic disorders for which PPI therapy is approved, daily standard-dose therapy (Table 2) is only recommended for initial, short-term treatment.11,21 Review patients who have been taking a PPI long term to evaluate if ongoing treatment is still indicated.

Table 1: Indications for PPIs and recommended duration of therapy
Diagnosis Initial PPI therapy


Daily, standard-dose PPI for 4–8 weeks.11,21

If response is inadequate despite regular standard-dose PPI therapy taken at the appropriate time, consider increasing to double-dose PPI for 4 weeks21 or referring for endoscopy or specialist review.11 If symptoms are well controlled, trial step-down therapy for maintenance.11,21

Functional dyspepsia

Helicobacter pylori eradication and gastric acid suppression are the two usual treatments; if one fails, try the other.21

  • Test for H. pylori and treat if positive.11,21
  • Trial PPI therapy, particularly if the main symptom is an epigastric burning pain. Use PPI therapy as per GORD, including step-down therapy for maintenance if symptoms are well controlled.11,21

Other options include trialling domperidone therapy (particularly if the main symptom is a feeling of discomfort and bloating), low-dose tricyclic antidepressant or anxiolytic medicines, cognitive or behavioural therapy, or psychotherapy.11, 21  

Note: Pharmacotherapy for functional dyspepsia has proved marginally more effective than placebo and any treatment only gives additional benefit to a small number of patients.11,21

Barrett's oesophagus

Use PPI therapy as per GORD, including step-down therapy for maintenance if symptoms are well controlled.22

A higher dose of PPI may be required but should be driven by symptom control and healing of oesophagitis when present. There is insufficient evidence to recommend the use of a PPI to prevent progression to oesophageal adenocarcinoma.11, 22

Note: Patients with Barrett's oesophagus are managed in consultation with a specialist.

Peptic ulcer disease (H. pylori related)

Twice-daily, standard-dose PPI as part of a 7-day first-line H. pylori eradication regimen with amoxcyllin and clarithromycin.11

Continue PPI in patients with gastric ulcers, large ulcers (> 1 cm) or complicated ulcers until endoscopy-confirmed healing.21  Ongoing maintenance is usually unnecessary after successful eradication of H. pylori.11

Peptic ulcer disease (NSAID related)

Daily, standard-dose PPI for 8–12 weeks to allow healing of ulcers. Eradication therapy is appropriate in H. pylori positive patients.11

If possible, discontinue NSAID and instead use paracetamol and physical therapies for pain management. Maintenance with PPI is indicated to reduce chance of relapse if patient requires an NSAID long term.11

Continuous, long-term PPI therapy has selective uses

Continuous, long-term PPIs have an important place in the management of some acid-related disorders.

  • Symptom management and prevention of complications in patients with GORD who have frequent, significantly troublesome symptoms that are not adequately controlled with step-down therapy.
  • Symptom management and prevention of complications in patients with severe oesophagitis, oesophageal stricture and oesophageal scleroderma. Higher PPI dose may be required for initial treatment.21
  • Healing and prevention of relapse in patients with H. pylori-related peptic ulcer disease if eradication therapy fails or is contraindicated.21
  • Prophylaxis in patients on long-term NSAIDs who are at high risk of NSAID-induced peptic ulceration.11,21
  • Symptom management, and healing and prevention of peptic ulcers in patients with Zollinger–Ellison Syndrome.21,23 Higher PPI dose may be required for initial treatment.23

Refer patients with complicated disease to a specialist.11,21

Step down PPI therapy for GORD

Gastro-oesophageal reflux is a normal physiological occurrence and it is important to reassure patients that the occasional symptoms are not a cause for concern and may not necessarily need medicines.3 Reflux is considered pathological, and is classed as GORD, when it leads to symptoms sufficiently troublesome in severity or frequency to significantly impact the patient's quality of life.3,11 Acid suppressing medicines such as PPIs and H2 antagonists, are effective for managing GORD, and relevant lifestyle measures should be suggested as adjunct therapy.3,11,21

Stepping down PPI therapy

Stepping down PPI therapy (click on image for larger version, 56 kB pdf)

If reflux symptoms occur twice-per-week or more, or significantly impact the quality of life of the patient, start PPI therapy.11,21

If symptoms are well controlled by initial PPI therapy, step down therapy.3,11,21 Up to 30% of patients may be able to stop PPI therapy immediately after the initial course of therapy without experiencing symptoms.3 Discuss with the patient options available for stepping down and consider their preferences in developing the step-down plan.

Consider rebound acid hypersecretion before stopping PPI

Rebound acid hypersecretion is defined as an increase in gastric acid secretion above pre-treatment levels after acid suppression therapy, and may occur after stopping PPI therapy.24,25 Symptomatic rebound acid hypersecretion entails difficult-to-manage gastro-oesophageal reflux symptoms and has been suggested as one of the factors contributing to the difficulty in discontinuing PPI therapy.24

There are conflicting data on whether discontinuation of PPI therapy is associated with symptomatic rebound acid hypersecretion. Two systematic reviews found no strong evidence for symptomatic rebound acid hypersecretion in patients with acid–peptic disorders but acknowledged heterogeneity between studies and methodological weaknesses.24,25 Some studies in healthy volunteers, particularly those who are negative for H. pylori infection,26,27 have shown reflux-like symptoms after withdrawal from PPI therapy.24,25

A step-down approach gradually reducing PPI dose before stopping, or using H2 antagonists or antacids to manage symptoms, may help manage rebound acid hypersecretion.19,24,25

Upfront discussions help manage patient expectations

When starting a patient with suspected GORD on PPI therapy, discuss upfront the anticipated duration of initial treatment and when they should return for review. Informing patients upfront that their dosage regimen may be adjusted at that stage will make for an easier conversation at review.

Advise patients on lifestyle modifications which may be helpful in reducing symptoms and the need for medicine. Also talk about medicines, both prescription and over the counter (OTC), which may exacerbate their symptoms.

Ask patients to return if symptoms persist or worsen while on PPI therapy as further investigations may be needed.

If symptoms are well controlled after initial treatment, stepping down PPI therapy is recommended.11,21 Because of their effectiveness, some people may feel apprehensive about changes, and anticipate the return of symptoms if the PPI is reduced or stopped. Reassure them by explaining the purpose of the step-down approach – to find the lowest dose of medicine that provides symptom relief and reduce the risk of adverse effects. Adverse effects and long-term safety of PPIs may be a greater concern to patients than health professionals realise.28

Be clear about any prescribing changes you make, how they may alter the patient's experience and how to manage them. Depending on your choice of step-down approach, it may be useful to advise patients on the appropriate use of antacids or H2 antagonists. Acknowledge that step-down therapy may need to be adjusted a few times for optimal symptom control and encourage regular reviews. While it is normal for symptoms to vary, remind the patient to get in contact if symptoms suddenly change.

Use lifestyle interventions as adjunct therapy

Guidelines recommend trialling lifestyle measures as the first step or as adjunct therapy in managing symptoms of gastro-oesophageal reflux.3,11,21 Certain foods, including spicy foods, citrus and carbonated beverages, as well as alcohol and tobacco are reported by many people to worsen reflux symptoms.29 Fatty and late-evening meals, chocolate and caffeine are also reported as common precipitants.11

Inform patients of these general suggestions but focus recommendations on identifying and avoiding their individual triggers while limiting unnecessary dietary restrictions.11

Controlled weight loss is effective for improving symptoms in patients with GORD and should be routinely recommended to people who are overweight.29-31 Elevating the bedhead can be helpful, particularly in patients with mostly night-time symptoms.3,11 ,29

Some medicines may exacerbate reflux symptoms

Undertake regular medicine reviews and educate patients about medicines which may induce or exacerbate symptoms of reflux. Some medicines that cause or worsen symptoms of GORD:12,21,32

  • anticholinergics
  • barbiturates
  • benzodiazapines
  • beta agonists 
  • bisphosphanates
  • calcium channel blockers
  • nitrates
  • NSAIDs
  • opioids
  • theophylline.

Refer complex GORD for endoscopy and specialist review

Endoscopy is not a sensitive diagnostic test for GORD as approximately two thirds of patients show no macroscopic evidence of oesophageal mucosal abnormalities.3,11 Empirical therapy with a PPI is an efficient way to confirm diagnosis in most patients presenting with typical GORD symptoms such as heartburn and regurgitation.

While endoscopy is not recommended as a routine test for GORD, it has an important role in some clinical scenarios.3,11,33

Consider early endoscopy

  • Patients with atypical or mixed symptoms which make the diagnosis unclear.3
  • Patients with risk factors11,12,22,33 for GORD complications (such as Barrett's oesophagus or peptic strictures)3,12,33
    • male
    • older age
    • short history of symptoms (especially in an older person)
    • severe/frequent symptoms
    • change in symptoms
    • or abnormally high waist–hip ratio

Refer for endoscopy

  • Patients with symptoms refractory to initial PPI therapy.3,11,21
  • If alarm symptoms are present.3,11,12,33
    • difficulty swallowing (dysphagia)
    • painful swallowing (odynophagia)
    • unexplained weight loss
    • persistent vomiting
    • blood in vomit (haematemesis) or faeces (melaena)
    • signs of anaemia

If a patient with GORD or suspected GORD experiences alarm symptoms, refer promptly for endoscopy and/or specialist review.

PPIs are safe but not without concern

PPIs are generally considered safe and are well tolerated by most patients. The most common adverse effects include headache, nausea, vomiting and diarrhoea, which are reported to be in the order of 1–5%;21,34 a rate little different from placebo.34

Reports about more serious, albeit rare, adverse effects associated with PPI use, such as fractures, pneumonia, enteric infections and acute interstitial nephritis, have raised concerns. Most of the evidence for these adverse effects comes from observational studies. Although these studies are insufficient to establish a causal relationship, they may provide clues about possible associations and warrant consideration. As with any medicines, judicious prescribing will mitigate the risk of adverse events, particularly in patients more vulnerable to medicine-related adverse effects such as older people and those with comorbidities.

Practice point

The absolute risk for fractures, pneumonia, enteric infections, and nutrient deficiencies is very low. Weigh the potential harms and benefits when prescribing a PPI and ensure patients are informed of the risks.3,11

Bone fractures

  • Recent meta-analyses report a small increase in risk of hip and spine fractures associated with PPI use mostly in older people, but acknowledged the potential role of confounding factors.35-37 Risk was present with both standard- and high-dose PPI,35 and for duration of use both  < 1 year and > 1 year.36
  • PPI therapy appears to have little to no effect on bone mineral density,38,39 suggesting any association between PPI use and fractures is not likely to be related to osteopoross.


  • Small increase in the overall risk of pneumonia in PPI users in a meta-analysis of 8 observational studies, although significant heterogeneity between studies was noted.40 Similar findings reported by a meta-analysis evaluating community-acquired pneumonia in PPI users.41
  • No association observed between PPI use and severe pneumonia requiring hospitalisation.42,43

Enteric infections

  • Increased susceptibilities to enteric infections caused by Salmonella, Campylobacter and Clostridium difficile have been reported.44,45 Recent meta-analyses support a weak association between PPI therapy and C. difficile infection but note significant heterogeneity.46

Vitamin and mineral deficiencies

  • PPI use has been associated with deficiencies in vitamin B12,47 iron and magnesium.48 In 2011, the TGA released a safety update acknowledging the potential association between prolonged use of a PPI and rare but serious hypomagnesemia-related adverse events. They recommended prescribers be vigilant to PPI-associated hypomagnesemia and noted that patients presenting with hypomagnesemia may require PPI discontinuation.49

Practice point

Be alert to symptoms that may suggest interstitial nephritis in PPI users.50 Consider risk for interstitial nephritis in PPI users with impaired renal function.3

Acute interstitial nephritis

  • PPI use implicated as a cause of acute interstitial nephritis;50-52 a 2007 systematic review concluded a low-prevalence association.51 These findings were supported by a recent case-controlled study of over half a million patients, which found a significantly increased risk of acute interstitial nephritis in current PPI users, compared with past users.52 Both studies noted a higher risk in older PPI users.51,52

Dosage equivalence for PPIs

Table 2: Dosage equivalence for PPIs11,12


Standard (full) dosage

Low (maintenance) dosage


20 mg once daily



30 mg once daily

15 mg once daily


20 mg once daily

10 mg once daily


40 mg once daily

20 mg once daily


20 mg once daily

10 mg once daily

A. Lowest available dose of esomeprazole is 20 mg, 10 mg omeprazole is an appropriate step-down option.

Expert reviewer

Dr Christopher Pokorny, Gastroenterologist, Conjoint Associate Professor in the Faculty of Medicine, University of New South Wales, Sydney, NSW

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