3.1.1. Vaccination

In many countries, community pharmacists now serve as immunizers for influenza, COVID-19, and other vaccines, dramatically expanding public access to immunization. Pharmacy-based vaccination services are currently authorized in over 50 countries worldwide, a sharp rise from about 20 countries a decade ago [11]. This global trend accelerated during the COVID-19 pandemic, with pharmacists being granted expanded vaccination authority across Europe, North America, and elsewhere to facilitate mass immunization efforts [11].

A systematic review and meta-analysis of 19 studies conducted in diverse settings found that incorporating a pharmacist intervention increased overall immunization rates by approximately 50% compared with usual care (pooled relative risk, 1.51) [15]. The roles that pharmacists play include patient education, addressing vaccine hesitancy, and providing convenient walk-in immunizations [15]. Pharmacies served as important sites for vaccination, particularly during the COVID-19 pandemic. For instance, in the United States, pharmacists and their teams administered an estimated 270 million COVID-19 vaccine doses, which is about 45% of all COVID-19 immunisations in the country [17]. At the height of distribution, the Federal Retail Pharmacy Program supplied up to 70–90% of daily doses during certain periods. This underscores the critical role of pharmacists in mass vaccination programs [17].

3.1.2. Smoking Cessation

Community pharmacies, clinics, and hospitals worldwide have implemented pharmacist-led smoking cessation programs, which have demonstrated promising results. For example, in Canada, a randomized study conducted in Newfoundland compared two pharmacist-managed smoking cessation programs: one intensive and one brief [18]. Both programs achieved high quit rates after six months (approximately 36% and 22% of participants, respectively), which is significantly higher than the ~7% quit rate reported in the general population without such assistance [18]. The difference between the intensive and shorter programs was not statistically significant, possibly due to the small sample size, but both were effective in helping smokers quit and were highly cost-effective. The cost per quit was significantly lower than that of other methods [18].

Community pharmacies in the UK have been supporting smoking cessation for a long time through the National Health Service [19]. The STOP study, a recent cluster-randomized trial involving 60 pharmacies in England and Wales, evaluated an intervention designed to increase service uptake and retention. The additional training intervention did not significantly improve the number of smokers enrolling or the quit success rate beyond usual care, but the study demonstrated that both trial arms achieved high levels of engagement and quit rates. More than 600 smokers in each group used the pharmacy service, and 42–43% of them successfully quit smoking for four weeks, as confirmed by biochemical verification. Patient retention was high (around 70% at four weeks), and both staff and customers reported positive experiences [19]. These findings suggest that standard pharmacy-based cessation services in the UK achieve high short-term quit rates (approximately 40% at one month), comparable to those achieved with intensive behavioural support combined with pharmacotherapy.

A multicentre randomized controlled trial in Thailand evaluated a cessation service provided by pharmacists, with and without the support of a mobile app. All participants received counselling and medication from community pharmacists over six months. The intervention group also used a smartphone app. During follow-up, both groups reported reduced cigarette consumption and higher abstinence rates (p < 0.05), underscoring the value of pharmacist support [20]. Notably, the final quit rates were not significantly different between the two groups, suggesting that counselling alone was just as effective as counselling plus the app in this setting. The app modestly improved program adherence (74 days vs. 60 days), but the key takeaway was that pharmacist-delivered support led to meaningful quit outcomes in a middle-income country context. Pharmacists supporting smoking cessation have demonstrated quit rates that are equal to or better than those achieved by other healthcare professionals across various studies and settings. This success is attributed to their expertise in medications, frequent patient interactions, and the ability to deliver personalized behavioural support.

In a prospective, randomised controlled study conducted across eight ambulatory pharmacies in Qatar, 314 adult smokers were assigned to either a structured pharmacist-led cessation program (comprising four counselling sessions over 2–4 weeks) or unstructured brief counselling [21]. At 12 months, the intervention group had a higher rate of continuous abstinence (23.9% vs. 16.9%; p = 0.257), although this difference was not statistically significant. However, participants who relapsed in the intervention group smoked significantly fewer cigarettes per day at 3 months (–4.7; p = 0.041) and at 6 months (–5.6; p = 0.018). Multinomial logistic regression analysis revealed that the only significant predictors of continued smoking after one year were a longer history of smoking and a higher baseline cigarette consumption [21]. Pharmacists in southern Portugal helped 135 smokers quit between 2009 and 2019 by combining motivational and behavioural counselling with pharmacotherapy, primarily nicotine replacement therapy [22]. The participants had an average age of 47.9 years, and 58.5% were male. At one month, 43.7% of participants remained abstinent, but this rate declined to 32.6%, 28.1%, and 20.7% at 3, 6, and 12 months, respectively. A multivariate analysis showed that the use of pharmacological aids and a higher number of face-to-face and phone follow-up sessions were both strongly associated with successful quitting (p < 0.001). [22].

3.1.3. Dietary Counselling

As part of their preventative services, community pharmacists have piloted initiatives to help people lose weight, eat healthier, and become more physically active. For example, an independent pharmacy in Virginia, USA, implemented a six-month pharmacist-led weight loss program focused on a high-protein, calorie-controlled diet combined with lifestyle coaching [23]. Alhomoud et al. systematically searched the literature to identify 29 retrospective or prospective studies (n = 6423; mean BMI 27–46 kg/m²) evaluating pharmacist-led weight-management interventions, primarily educational counselling, with medication recommendations in five studies, and extracted changes in body weight, BMI, or waist circumference [24]. Twenty-six studies reported significant weight-loss outcomes (most over periods < 6 months), but multidisciplinary collaboration was infrequent, and study quality was generally poor. In a cross-sectional survey of Saudi community pharmacists reported that although 73% of respondents acknowledged obesity as a critical health issue and 76%–83% routinely counselled on diet and physical activity, only 31% had formal weight-management training and just 33% regularly dispensed weight-loss products; key barriers included inadequate staffing (39%), lack of private consultation areas (37%), and absence of dedicated remuneration (49%) [25].

Another recent effort to combat obesity at a cardiology clinic highlighted how helpful pharmacists can be in monitoring weight-loss medications and providing lifestyle advice. In a 2023 trial, clinical pharmacists led a weight management program for high-risk cardiac patients who were taking GLP-1 agonist drugs such as semaglutide or liraglutide, alongside receiving guidance on diet and exercise [26]. Out of 59 patients who enrolled, 31 completed six months of therapy. All 31 patients lost at least 5% of their body weight, with an average weight loss of 12.6%. Participants also experienced reductions in blood pressure (−9/−2 mmHg), blood lipids (LDL decreased by 18 mg/dL; triglycerides by 29 mg/dL), and improved blood glucose control (mean HbA1c reduction of 0.6%). The researchers concluded that pharmacist supervision of anti-obesity medications contributed to clinically significant weight loss and improved cardiometabolic risk factors in this high-risk population.

A systematic review of 25 randomized controlled trials evaluated the effects of brief physical activity counselling interventions delivered outside primary care on activity levels, adherence, and related outcomes. A meta-analysis found that, at medium-term follow-up, these interventions increased self-reported physical activity by an average of 34 min per week (95% CI: 9–60 min) and daily step counts by 1541 (95% CI: 433–2649), although evidence for long-term effectiveness remains limited [27].

In a prospective quality-improvement evaluation of the VA Tennessee Valley Healthcare System’s MOVE! program, 40 patients under the care of a clinical pharmacy specialist (CPS) received pharmacist-led medication assessments and telehealth follow-up over six months. These patients were compared to 29 individuals who received standard preventive care. The CPS-run clinic helped patients lose an average of 3.6 ± 5.7 kg (p < 0.001), with 25% of patients losing at least 5% of their total body weight. In contrast, the preventive medicine program (PMP) group lost only 1.6 ± 6.0 kg (p = 0.15), with 17.2% of patients achieving at least 5% weight loss. These findings indicate that the clinic significantly supported weight loss and improved access to obesity medication services [28].

3.1.4. Harm Prevention

As medication experts, pharmacists have become key players in reducing medication errors and the harm they cause. Numerous high-quality studies—including RCTs, quasi-experiments, and observational studies have evaluated pharmacist-led initiatives aimed at improving medication safety over the past decade. This section compiles evidence on pharmacists’ contributions to preventing prescribing, dispensing, and administration errors, as well as their broader harm-reduction roles, including overdose prevention and the reduction of drug misuse.

Pharmacist engagement has consistently led to significant reductions in prescribing errors and improvements in prescription quality. In primary care, the UK cluster-RCT PINCER (Pharmacist-led Information Technology Intervention for Medication Errors) demonstrated that a pharmacist-led intervention—consisting of electronic prescription review, prescriber feedback, and educational outreach—substantially improved prescribing safety. The initial study (pre-2015) revealed notable benefits, and a large-scale rollout across 343 practices (covering 3 million patients) between 2015 and 2017 confirmed its effectiveness [29]. At six months, the rate of high-risk prescriptions was approximately 17% lower than before the intervention (adjusted odds ratio ~0.83), and this reduction persisted at around 15% after 12 months. The most improved indicators were those associated with gastrointestinal bleeding risk (around 24% reduction). These findings underscore the value of pharmacist-led audit-and-feedback systems in outpatient settings to prevent potentially harmful prescribing [29].

In hospital settings, clinical pharmacists involved in care teams and medication reviews have shown measurable benefits. A Danish multicentre RCT involving 1467 inpatients (median age 72) evaluated a complex pharmacist-led intervention during care transitions. Pharmacists conducted thorough medication reconciliation upon admission and again at discharge [30]. The 30-day readmission rate was significantly reduced (hazard ratio 0.62; 95% CI 0.46–0.84) in the intervention group compared to usual care. At 180 days, the overall number of readmissions remained lower (HR ~0.75). Although drug-related readmissions did not reach statistical significance, the combined outcome of any readmission or emergency department visit improved significantly (Number Needed to Treat (NNT) ≈ 12) [30]. Targeted medication reviews by pharmacists in specialized settings have also been effective in reducing errors. For instance, a retrospective study from South Korea examined investigational cancer therapy trials, where pharmacists carefully reviewed drug orders. During the pharmacist intervention phase, the prescription error rate declined from 6.1% to 4.7%, representing a reduction of nearly 25% across more than 12,000 orders. In multivariate models, pharmacist involvement was associated with significantly fewer errors, even after adjusting for trial complexity [31]. Intravenous drug orders were more prone to errors than oral ones, and pharmacists were particularly valuable in identifying IV-related mistakes. Blinded trials had fewer errors than open-label ones, underscoring the need for pharmacist oversight.

Pharmacists integrated into multidisciplinary ward teams can intercept prescription errors in real time. A US study in an academic hospital assessed pharmacist-led discharge medication reconciliation for internal medicine patients (mean age 60; n = 31) [32]. Pharmacists identified errors in 68% of discharge summaries, averaging 1.3 errors per patient. The most common issues were therapeutic duplications and omissions due to access barriers. Errors were classified by severity, with 77.5% considered potentially serious or life-threatening if uncorrected—all of which were resolved before discharge. Notably, 35% of these errors would likely have led to emergency visits or readmissions if left unaddressed. A cost-avoidance analysis estimated that this one-month intervention saved $24,784 in healthcare costs, while pharmacist labour costs were under $1000. In Jordan, a recent RCT (2025) examined pharmacist-led medication reconciliation for elderly inpatients (n = 128). At admission, pharmacists obtained a Best Possible Medication History, corrected discrepancies, and ensured an accurate discharge list. Patients in the intervention group had approximately 70% lower odds of readmission or emergency department visits within 30 days post-discharge compared to the control group [33]. Most errors were corrected before discharge, and 94% of pharmacists’ recommendations were accepted by physicians. This led to significantly fewer post-discharge hospital encounters.

Pharmacists’ activities in public health-oriented harm reduction have grown beyond merely dispensing and assessing medications. They are now more involved in addressing the opioid overdose crisis and pharmaceutical misuse. Community pharmacists are increasingly participating in programs aimed at preventing drug-related harm at the population level, such as naloxone distribution, syringe exchange programs, and opioid stewardship initiatives. Preventing opioid overdoses is a major area of focus. Since 2015, several jurisdictions have authorized pharmacists to dispense naloxone (the opioid overdose antidote) without a physician’s prescription through collaborative practice agreements or standing orders. This policy has been shown to save lives. One study of the U.S. population in 2019 examined opioid overdose death rates in states with different naloxone access laws. It found that overdose deaths declined significantly in states where pharmacists were permitted to dispense naloxone directly. In the three years following the implementation of such laws, those states saw approximately 0.387 fewer deaths per 100,000 people compared to states without such policies [34].

Pharmacists also play a vital role in opioid use prevention and stewardship. They have implemented opioid stewardship programs in healthcare systems to ensure the safe prescribing and monitoring of opioids. A scoping review identified dozens of studies examining pharmacists’ roles in managing opioid use across hospitals, primary care, and community settings. In the majority of these studies, pharmacist-led interventions improved at least one outcome related to opioid use [35]. These improvements included reductions in opioid prescriptions or dosages, increased adherence to prescribing guidelines, and fewer patients receiving dangerous combinations of opioids and benzodiazepines. Pharmacists often managed medication therapy for individuals with chronic pain, identified patients at high risk for misuse, educated prescribers on best practices, and developed opioid tapering plans. One example involved a hospital that reported substantial reductions in high-dose opioid prescribing and concurrent opioid/benzodiazepine use after integrating a clinical pharmacy specialist into its pain management team [36]. Thousands of individualized patient interventions were also documented during this period [36]. Community pharmacists are also active in harm reduction. Surveys indicate that many are willing to participate in needle and syringe exchange programs, which provide clean injection supplies and safe disposal for used needles. These programs help reduce the spread of blood-borne diseases among people who inject drugs [37].