Patients with dually diagnosed mental illness and substance use disorder are at high risk for suicidal behaviour (Abroms and Sher, Reference Abroms and Sher2016). For example, substance use disorders are a significant predictor of suicide attempts in patients with bipolar disorder, and the risk of suicide in patients with co-occurring bipolar and alcohol use disorder is roughly twice than that of those without alcohol use disorder (Dalton et al., Reference Dalton, Cate–Carter, Mundo, Parikh and Kennedy2003). Patients with dual diagnosis are also more likely to have medical and neurological comorbidities, such as pain disorders and traumatic brain injuries, which further increase risk for suicidal behaviours (Abroms & Sher, Reference Abroms and Sher2016).

The COVID-19 pandemic may lead to relapse or exacerbation of pre-existing dual disorders and to the onset of new dual disorders. The COVID-19 crisis is associated with anxiety, fear of contagion, uncertainty, social isolation, chronic stress, economic difficulties, and other psychosocial issues which may lead to relapse or worsening of depressive, anxiety, substance use, and other psychiatric disorders in vulnerable populations, especially in individuals with dual disorders (Sher, Reference Sher2020). For example, a recent study in China showed that during the COVID-19 pandemic 19% of abstinent alcohol users and 25% of abstinent smokers relapsed (Sun et al., Reference Sun, Li, Bao, Meng, Sun, Schumann, Kosten, Strang, Lu and Shi2020). Also, 32% of regular alcohol drinkers increased alcohol consumption and 20% of regular smokers increased smoking during the pandemic. The American Medical Association Issue Brief published on 20 July 2020 stated that more than 35 U.S. States reported increases in opioid-related mortality during the COVID-19 pandemic (American Medical Association, 2020).

The COVID-19 pandemic may also lead to the onset of new dual disorders. Distressed, anxious, and depressed individuals may start using alcohol and drugs. It is important to note that substance use can lead to immune system, respiratory, and pulmonary alterations and may increase susceptibility to COVID-19.

Feelings of fear and anxiety may hold people back from seeking or continuing treatment for dual disorders. When psychiatric disorders go untreated, substance abuse typically worsens, and when someone starts using more drugs or alcohol, their psychiatric disorders worsen. The Coronavirus disease crisis may increase suicidality among patients with dual disorders during and after the pandemic. It is a perfect storm situation: the COVID-19 pandemic may increase suicide risk in persons with dual disorders who are already at elevated suicide risk.

To reduce suicides among individuals with dual disorders in the COVID-19 epoch we need to

• improve recognition of dual disorders. Unrecognised and untreated individuals with dual disorders may be at a specially high suicide risk;

• screen dual disorders patients for suicidal ideation;

• adequately treat dual disorders;

• prevent a relapse when the patient is in remission; this is especially important in the stressful COVID-19 era;

• treat comorbid medical and neurological disorders;

• provide social support; it is vital to reduce social isolation/loneliness during the COVID-19 epidemic;

• provide dual disorders patients with information about suicide prevention hotlines and other available mental health resources;

• reduce access to lethal means, if possible.

Psychiatric consequences of the COVID-19 disaster including increase in suicides are probably to be present for a lengthy time and peak later than the actual COVID-19 pandemic. Although suicide prevention is a very difficult task, clinicians are expected to make every effort to prevent suicide in their patients.