@ned there are several that are commonly used, oral meds are usually the first choice but if the intended recipiant is unwilling to take oral then it's an IM injection. First line is a fast acting benzodiazapine, usually lorazepam, if that's unsucessful and the patient has had them before it'll be an antipsycotic, usually haloperidol, risperidone (oral) or aripiprazole. Occasionally olanzapine, but no one in the UK makes it so cost becomes prohibitive. In extreme cases Accuphase will be used (a fast acting, long duration version of zuclopentixol) is used but that is only really a last resort, effects can last up to 48 hours and often during this time a (new) antipsychotic, often a long acting zuclopentixol depot injection will be commenced.