Background: Schizophrenia requires prolonged use of antipsychotics, yet accessibility challenges often hinder adherence in low- and middle-income nations.

Objective: This study examined factors influencing drug accessibility and their effect on treatment adherence in North-Western Nigeria.

Method: A cross-sectional survey was conducted among 865 individuals diagnosed with schizophrenia across seven states. Data was collected using a standardized questionnaire, including the Morisky Medication Adherence Scale (MMAS-8). Analysis employed SPSS version 26 with descriptive statistics, Chi-square tests, and logistic regression, using a significance threshold of p < 0.05.

Results: The mean age was 42.3 ± 11.2 years, and 53.9% were male. Adequate drug accessibility was reported by 53.7%, while 46.3% experienced poor accessibility due to high costs (75%), stock-outs (52.5%), and distance to facilities (53.1%). Adherence levels were classified as good (44.9%), moderate (32.8%), and poor (22.3%). Poor accessibility was significantly associated with low income (AOR = 3.42), rural residence (AOR = 2.18), and unemployment (AOR = 1.87). Predictors of non-adherence included structural barriers (high costs, frequent stock-outs, distance to facilities) and clinical factors (adverse effects, polypharmacy), as well as limited education. Patients with adequate accessibility were nearly three times more likely to adhere (AOR = 2.94, 95% CI = 1.74–4.53).

Conclusion: Drug accessibility strongly influences adherence to antipsychotics among people with schizophrenia. Strengthening medicine supply chains, subsidizing costs, and expanding community-based support are vital for improved outcomes.

Implication for Nursing Practice: Nurses play a central role in improving adherence by addressing accessibility barriers, providing patient and family education, and advocating for affordable and consistent antipsychotic availability.