Neurotransmitters, receptors and signalling

Meet the patient — one man, four complaints, four receptors

A 34-year-old man on a first-generation antipsychotic arrives at medication-review clinic with four things he has never mentioned before. His mouth is "like sandpaper". He greys out standing up. His hands shake on the cup. There is milk on his shirt.^[10][15]

He has not developed four new illnesses. He has one drug sitting on four receptors: M1 (dry mouth), alpha-1 (postural drop), nigrostriatal D2 (tremor), tuberoinfundibular D2 (galactorrhoea).^[10][15]

That translation — complaint to receptor to anatomical address — is the whole topic. Examiners ask it forwards ("what will this drug do to him?") and backwards ("why is he leaking milk?"). Learn it once, in both directions.^[1][10]

References20ShowHide

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