There is described a method for increasing the maximal tolerated dose and thus the efficacy of an acetyl choline esterase inhibitor (AChEI) in a patient suffering from an Alzheimer type dementia by decreasing concomitant adverse effects by administration of said AChEI in combination with a non-selective, peripheral anticholinergic agent, whereby an enhanced acetyl choline esterase inhibition in the CNS of said patient is achieved and alleviation of the symptoms of Alzheimer type dementia in said patient is thereby improved to a greater extent. The use of a non-selective, peripheral anticholinergic agent (nsPAChA) for the preparation of a pharmaceutical composition for increasing the maximal tolerated dose and thus the efficacy of an acetyl choline esterase inhibitor (AChEI) in a patient suffering from an Alzheimer type dementia and pharmaceutical compositions comprising a non-selective peripheral anticholinergic agent of formula II as illustrated in the description and an acetylcholine esterase inhibitor are also described.