Why do extrapyramidal and antimuscarinic side effects occur during treatment for mental health?

Med side effects: Extrapyramidal symptoms include akathisia (severe restlessness), painful muscle contractions (dystonia), Parkinsonian symptoms and in chronic cases, permanent abnormal muscle contractions (tardive dyskinesia). EPS is usually caused by antipsychotic medications. Anticholinergic side effects include dry mouth, confusion and blood pressure changes. The latter can be seen with several types of meds.