A high proportion of suicides visit their medical provider in the month prior to death, but depression, suicidal thoughts, and substance use are seldom addressed. For the clinicians routinely treating a substantial patient population with allergic diseases, there are additional concerns, as allergy has been linked with both depression and suicidal behavior. While psychotropic medications may affect diagnosis of allergies, medications used to treat allergies impact mood and behavior. Thus, we present an overview of the overlap of allergic rhinitis with depression and suicidal behavior in adults, based on clinical and epidemiological data, and our research and clinical experience. In summary, we suggest: 1) inquiring among patients with allergies about personal and family history of depression, substance use disorders, suicidal ideation and attempts 2) increased mindfulness regarding the potential effects of allergy medications on mood and behavior; and 3) for people identified with certain types of depression or increased suicide risk, a systematic multilevel collaborative approach. While for practical reasons the majority of patients with depression will continue to be treated by general or family practitioners, the allergy-treating provider should always consider integrated care for bipolar, psychotic or suicidal depression and incomplete remission, or relapsing and highly recurrent course. While awaiting results of much needed basic and clinical research to guide clinical approach for patients with comorbid allergic rhinitis and depression, the simple steps recommended here are expected to improved clinical outcomes in depression, including, on a large scale, reduced premature deaths by suicide.