I asked the resident how he planned to help her while she was in the hospital. After a pause, he suggested meekly, “Start her on an antidepressant?”

I could tell he knew how ridiculous it sounded.

As doctors, we want to help people, and it can be hard for us to admit when our tools are limited. Antidepressants may seem like an obvious solution, but only about 40 percent to 60 percent of patients who take them feel better. And while nearly one in 10 Americans uses antidepressants, there is very little convincing evidence to show that they reduce suicide.

This is because many of the problems that lead to suicide can’t be fixed with a little extra serotonin. Antidepressants can’t supply employment or affordable housing, repair relationships with family members or bring on sobriety.

Suicide prevention is also difficult because family members rarely know someone they love is about to attempt suicide; often that person doesn’t know herself. The flight attendant’s extensive planning is unusual; much more common is the grabbing of whatever is at hand in a moment of despair.

According to a 2016 study, almost half of people who try to kill themselves do so impulsively. One 2001 study that interviewed survivors of near-lethal attempts (defined as any attempt that would have been fatal without emergent medical intervention, or any attempt involving a gun) found that roughly a quarter considered their actions for less than five minutes. This doesn’t give anyone much time to notice something is wrong and step in.

Nonetheless, mental health providers perpetuate the narrative that suicide is preventable, if patients and family members just follow the right steps. Suicide prevention campaigns encourage people to overcome stigma, tell someone or call a hotline. The implication is that the help is there, just waiting to be sought out.

But it is not that easy. Good outpatient psychiatric care is hard to find, hard to get into and hard to pay for. Inpatient care is reserved for the most extreme cases, and even for them, there are not enough beds. Initiatives like crisis hotlines and anti-stigma campaigns focus on opening more portals into mental health services, but this is like cutting doorways into an empty building.