Emotion suppression (also known as flat affect, apathy, or emotional blunting) is medically recognized as a flattening or decrease in the intensity of one's current emotional state below normal levels.    This dulls or suppresses the genuine emotions that a person was already feeling prior to ingesting the drug. For example, an individual who is currently feeling somewhat anxious or emotionally unstable may begin to feel very apathetic, neutral, uncaring, and emotionally blank. This also impacts the degree to which the person will express their emotional state through body language, tone of voice, and facial expressions.
It is worth noting that although a reduction in the intensity of one's emotions may be beneficial at times (e.g., the blunting of an anger response in a volatile patient), it may be detrimental at other times (e.g., emotional indifference at the funeral of a close family member). 
Emotion suppression is often accompanied by other coinciding effects such as motivation suppression, thought-deceleration, and analysis suppression. It is most commonly induced under the influence of moderate dosages of antipsychotic compounds, such as quetiapine, haloperidol, and risperidone.   However, it can also occur in less consistent form under the influence of heavy dosages of dissociatives   , SSRI's   , and GABAergic depressants  .
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