5e SRD:Potion of Growth
From D&D Wiki
|This material is published under the OGL|
When you drink this potion, you gain the “enlarge” effect of the enlarge/reduce spell for 1d4 hours (no concentration required). The red in the potion's liquid continuously expands from a tiny bead to color the clear liquid around it and then contracts. Shaking the bottle fails to interrupt this process.