The Whitworths of Arizona, bringing science to you in everyday language.

Thursday, August 29, 2013

LBD and Drugs, Part 7: Dementia Drugs

The PD drugs discussed last week and dementia drugs have conflicting actions. That is, drugs that improve motor function are likely to impair cognitive function. Conversely, drugs that improve cognition are likely to decrease mobility.  In each case, families and physicians have to find a balance of treatment that works for each person. Last week’s blog discussed first half of this balancing act. This blog is about dementia drugs, the other part of this balancing act.

Drugs used to treat the cognitive symptoms of LBD have been used with Alzheimer’s for many years. Research has shown them to be even more effective with LBD. However, due to the slowness of our drug accrediting system, only a few are approved by the FDA for treatment of PDD and none for treatment of DLB. (See the May 17, 2013 blog for the difference/similarity between PDD and DLB.) Lewy-savvy physicians regularly prescribe these drugs to treat LBD. These drugs treat all LBD symptoms, not just cognition. They act in one of two ways:

Acetylcholine preservation:  Aricept, Exelon and Razadyne are all cholinesterase inhibitors (AChEIs). They inhibit a chemical that moves acetylcholine out of the brain cells.  Only Exelon has been approved by the FDA for use with PDD. People often have the following concerns about these drugs:

Glutamate preservation: Namenda acts to preserve the chemical glutamate, which also helps cognition.  It doesn’t interact with PD meds the way AChEIs do, but it is usually less effective alone. However, it can be used with the AChEIs to improve their effectiveness. (Drugs with similar actions cannot be used together safely. Because Namenda acts on a different chemical, it CAN be used with other dementia drugs and that has been its main value so far. Like other dementia drugs, it requires live cells to work.

Concern: These drugs only last a few years and so I don’t want to start until I really need them.

  • Fact: It is true that once a nerve cell is so weak that it can no longer produce acetylcholine, these drugs are not effective. However, AChEIs do not damage the cells; the Lewy bodies do that. AChEIs neither fight Lewy bodies nor protect the nerve cells. They simply extend the cells ability to function by preserving acetylcholine.  These drugs may not be very effective with MCI, but once dementia appears, they can improve one’s quality of life.  Starting them early usually means that they will be useful longer than if you wait to start them when your loved one has fewer functioning brain cells.

Concern: I’ve been told they have serious side effects like nausea, diarrhea, vomiting and other GI problems.

  • Fact: Oral doses of these drugs can cause serious GI side-effects. However, both Aricept and Exelon come in patches, which eliminates most of these symptoms.

Concern: They are expensive. I’m afraid we won’t be able to afford them.

  • Fact: These drugs are expensive. However, some companies now sell larger doses that cut down the cost considerably. Even if you don’t need the larger dose, you may be able to cut a larger size pill in half. Patches should not be cut in half. Some companies offer discounts to people who meet their criteria.

Concern: I have PD. Can I take these drugs? Won’t they increase my PD symptoms?

  • Fact: They may. Since all AChEIs work to improve the level of acetylcholine, they change its ratio to dopamine and thus, may cause motor dysfunctions. You will need to work with your physician to find a happy medium between mobility and cognition. 

Concern: My father has Active Dreams. Will these drugs help with these?

  • Fact: All of these drugs treat LBD’s symptoms in general, which includes Active Dreams and other acting-out behaviors. 

Summary: These drugs can improve cognitive function and other LBD symptoms but they may do so at a cost of decreasing mobility. They also lose effectiveness as live brain cells decrease. Decreasing stress and behavior management may work equally well and be effective longer.

The authors of this blog are not physicians. We report what we and other caregivers have learned by experience, from physicians and from the literature. This blog is informational only. You should always talk with a physician about individual issues.

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