But this dryness is not due to dehydration. Instead, dry mouth happens due to the impact of delta eight at the salivary glands. Brain Fog Brain fog and grogginess may arise if this compound is taken in higher-than-ordinary quantities. Note that brain fog and grogginess do now not happen if the substance is taken in endorsed doses. Dry Eyes Dry eyes may additionally arise if an excessive amount of delta-eight-THC changed into taken.