There really isn't enough information to answer this question, and the information that is required should not be posted here.
As a general answer, digestive disorders can change the rate and time of absorption. These changes can provide defenses to a DUI charge in the event these changes make it difficult or impossible to relate the BAC at time of testing back to the BAC at the time operation (unless you are in a state that penalizes BAC within a certain period after driving.) For breath tests there can be other problems.
For blood tests absorption rate changes do not allow a higher reading than the amount consumed. That is because the BAC is a ration established by the amount of alcohol availabel as compared to the amount of blood. That being said you can get a higher or lower BAC from the same amount of alcohol due to slow or rapid absorption.
In a breath test a rapid absorption can result in a falsely higher BAC reading during the time of absorption due to arterial-venous BAC differentials. (Almost all breath tests will be falsely high during absorption, but rapid absorption can cause a greater differential.)
Also, there may be other metabolic changes associated with the illness that caused the colitis, and those conditions may affect breath tests by giving falsely high readings.
You need to have the case handled by a top flight DUI lawyer. Go to the Colorado list of DUI lawyers at the link below as a starting place.
Wayne R. Foote, Esq.
Board Certified OUI Defense Law Specialist
by the National College for DUI Defense, Inc.
Law Offices of Wayne R. Foote, PA
344 Mt. Hope Ave
Bangor, ME 04401
(207) 990-5858 (fax)
"Injustice anywhere is a threat to justice everywhere." M. L. King, Jr.
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