When it comes to describing a large amount or excessive dosage of something, there are several synonyms that can be used instead of the phrase "heavy dose." These synonyms include "massive amount," "huge dose," "overwhelming quantity," "excessive dose," "large dosage," and "enormous quantity." These phrases can be helpful in providing more descriptive language when discussing medication, supplements, or other substances that require precise dosing. Moreover, these synonyms can also be used in non-medical contexts to describe intense experiences or strong emotions, such as a "massive amount of stress" or an "overwhelming quantity of joy".