Dysphoria is a profound state of unease or dissatisfaction. In a psychiatric context, dysphoria may accompany depression, anxiety, or agitation. The term is often used to refer to gender dysphoria, experienced by people whose gender identity does not align with their biological sex, and who may undergo sex reassignment surgery. Common reactions to dysphoria include emotional distress; in some cases, even physical distress. The opposite state of mind is known as euphoria.

Some drugs can produce dysphoria, including κ-opioid receptor agonists like salvinorin A (the active constituent of the hallucinogenic plant Salvia divinorum), butorphanol, and pentazocine, μ-opioid receptor antagonists such as naltrexone and nalmefene, and antipsychotics like haloperidol and chlorpromazine (via blockade of dopamine receptors), among others. Depressogenic and/or anxiogenic drugs may also be associated with dysphoria.

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