To the Editor:

I am the editor of “The Dangerous Case of Donald Trump: 27 Psychiatrists and Mental Health Experts Assess a President.” We represent a much larger number of concerned mental health professionals who have come forward to warn against the president’s psychological instability and the dangers it poses. We now number in the thousands.

We are currently witnessing more than his usual state of instability — in fact, a pattern of decompensation: increasing loss of touch with reality, marked signs of volatility and unpredictable behavior, and an attraction to violence as a means of coping. These characteristics place our country and the world at extreme risk of danger.

Ordinarily, we carry out a routine process for treating people who are dangerous: containment, removal from access to weapons and an urgent evaluation. We have been unable to do so because of Mr. Trump’s status as president. But the power of the presidency and the type of arsenal he has access to should raise greater alarm, not less.

We urge the public and the lawmakers of this country to push for an urgent evaluation of the president, for which we are in the process of developing a separate but independent expert panel, capable of meeting and carrying out all medical standards of care.