Yes, gastroparesis can delay drug absorption from the intestine and this can cause lower than expected levels of drugs in
the blood and their metabolites in
. So, yes, if you have severe gastroparesis and are on low morphine dose, then you can get a false negative result. Please consult your doctor regarding this. Hope this helps. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you.