As illustrated in Fig. 1, the initial search in the four databases yielded 191 articles. After removing the duplicates (n = 22), 169 records were initially screened by title and abstract, of which 127 were excluded. Of the remainder 42 records that were fully reviewed, only 19 were eligible for inclusion. A total of 21 articles from the complementary manual search were also eligible for inclusion, yielding a total of 40 articles included in this scoping review.

PRISMA diagram reporting the databased used, the number of records screened by title and abstracts, and full-text articles retrieved

Over half of the studies (n = 23/40, 57.5%) were conducted in North America. The other studies originated from the Netherlands (n = 3/40, 7.5%), Spain (n = 2/40, 5%), Australia (n = 2/40, 5%), Thailand (n = 1/40, 2.5%), Bulgaria (n = a 1/40, 2.5%), Japan (n = 1/40, 2.5%), Brazil (n = 1/40, 2.5%), Bosnia and Herzegovina (n = 1/40 = 2.5%), Israel (n = 1/40, 2.5%), and Sweden (n = 1/40 = 2.5%) and only three studies were conducted in Arab countries (KSA, Kuwait and Syria/Jordan).

Half of the studies were conducted in hospitals or affiliated outpatient clinics (n = 20/40, 50%), while the other half were conducted in community pharmacies (n = 19/40, 47.5%) or nursing homes (n = 1/40, 2.5%). The majority of the studies (24/40, 60%) reported on pharmacist-led specific/single depression interventions or management strategies [22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45], four studies (n = 4/40, 10%) reported on pharmacist-led comprehensive pharmaceutical care services for patients with depression [46,47,48,49], and 12 studies (n = 12/40, 30%) reported on pharmacists’ collaborative care practices in depression management [50,51,52,53,54,55,56,57].

As summarized in Table 2, two main pharmacist-led depression interventions/services were provided: Among the 24 studies within this category (category 1), 13 studies reported on depression treatment education/monitoring (54.2%, 13 out of 24) [19, 23, 24, 27, 28, 33, 35,36,37,38,39,40,41]. and 11 studies reported on depression screening (11/24, 45.8%) [22, 24,25,26, 29, 30, 33,34,35,36, 38]. Outcomes assessed in these studies included positive depression screenings, referrals to GPs and/or other healthcare providers, depression symptoms and severity, and medication adherence. Although various types of screening tools were used, the 9-question Patient Health Questionnaire (PHQ-9) was the most common across all the studies. All the screening interventions positively identified individuals at risk or with depression (between 4–70.7% of individuals screened), and the majority resulted in referrals to GPs or other healthcare providers. Furthermore, six patients out of the 11 positively screened for depression (54.5%) were referred either for further assessment or for starting treatment [22, 26, 30, 33, 35, 38], The most commonly reported outcome for pharmacist-led depression treatment education/monitoring interventions was adherence rate (9/13, 69.2%) [28, 31, 32, 37, 39,40,41,42, 45]. Prescription refills, clinic visit frequency, patient self-report, electronic pill containers, and percentage of missed doses were used to assess adherence. The majority of the studies reporting adherence rate as an outcome (7/9, 77.8%) showed improvements depression treatment adherence as a result of the intervention [28, 31, 32, 39, 41, 42, 45]. Depression symptom severity and quality of life were the second most commonly reported outcome for pharmacist-led depression treatment education/monitoring interventions (8/13, 61.5%) [23, 27, 33, 37, 42,43,44,45]. The majority of these studies (6/8, 75%) showed the pharmacist intervention resulted in improvement in depressive symptoms, decrease in symptom severity or improved quality of life [23, 27, 31, 37, 44, 45]. Other outcomes reported in the studies under this category included depression knowledge, attitudes, and beliefs (KAB) and patient satisfaction with the services [28, 35, 36, 39]. On the other hand, some studies reported no significant differences on patient-related outcomes [37, 40, 42, 56].

As summarized in Table 3, all the studies reporting on pharmacist-led comprehensive depression management strategies showed a significant impact on patient outcomes, including improvement in depression severity, reduction in antidepressant side effect occurrence, timely detection and management of potential or actual drug-related problems (DRPs), enhancement of patients’ quality of life, and promotion of adherence [46,47,48,49]. In the majority of these studies (3/4, 75%), pharmacists employed a comprehensive medication therapy management approach when providing pharmaceutical care to people with depression [28,29,30,31,32,33,