Nutcases is an informal term used to describe individuals who behave in an irrational or eccentric manner. There are several synonyms for the word nutcases, including lunatics, crazies, kooks, weirdos, oddballs, and maniacs. Other possible alternatives include fanatics, zealots, eccentrics, and loonies. Each of these terms carries a slightly different connotation and degree of seriousness, but all generally suggest someone who is mentally unstable or unpredictable. It's important to use these words with caution and sensitivity, as they can be hurtful or offensive to individuals struggling with mental health. In many cases, it's best to avoid judgemental language altogether and instead focus on respectful and compassionate communication.