DEAR DR. DONOHUE: I am 77 and was recently diagnosed with Parkinson’s disease. I take Sinemet and Azilect. I have NO tremors. However, I have stiffness in my legs, difficulty getting up from the seated position and loss of balance. I understand there is no cure. What is the recommended treatment? Can I expect a normal life span? — J.G.

ANSWER: The cardinal features of Parkinson’s disease are muscle rigidity, bradykinesia and resting tremor.

Muscle rigidity means that muscles lose their fluid movement. Bending the arm, for example, consists in a series of small, stiff motions like a ratchet moving from one groove to the next.

Bradykinesia is small, slow movements. It makes actions like buttoning a shirt, tying shoes or controlling a computer mouse difficult. Patients describe it as muscle weakness or klutziness. Trouble rising from a chair is an example of bradykinesia.

The Parkinson’s tremor, not always part of a patient’s signs, is a resting tremor. It occurs, for example, when the hands are in the lap. The index finger constantly rolls over the thumb. Other Parkinson’s signs are an expressionless face, decreased blinking, difficulty swallowing and loss of balance. All these signs don’t affect every patient, and the degree to which they do varies from patient to patient.

A deficiency of the brain chemical dopamine brings about all these signs and symptoms. Dopamine is a messenger chemical involving parts of the brain concerned with movement. Medicines used for treatment are, for the most part, ones that boost the brain’s level of dopamine. Sinemet, for example, is the combination of two medicine, levodopa and cardiodopa. Levodopa is a precursor of dopamine. Dopamine cannot penetrate into the brain, but levodopa can. When it arrives there, it is changed into dopamine. Cardiodopa slows the breakdown of dopamine. Your Azilect (rasagiline) is medicine that also puts a halt to the degradation of dopamine. There are many more drugs. Which is best depends on your symptoms.

It’s difficult to predict the lifespan of one with Parkinson’s. If the disease is not disabling, lifespan is near normal. Stay as active as you possibly can.

DEAR DR. DONOHUE: Yesterday my daughter called me in near panic, telling me to stop drinking Diet Coke because it contains phenylalanine, a terrible poison. I drink two Diet Cokes a day. I also drink Crystal Light lemonade and Suisse Mocha, both of which contain phenylalanine. Is water my only alternative? — L.E.

ANSWER: Phenylanaline is a danger only to phenylketonurics — people who have the genetic illness PKU, phenylketonuria. You are not a phenylketonuric, and you do not have PKU. People with PKU don’t have the enzyme that breaks down the amino acid phenylalanine. Blood levels of it rise, and high levels cause brain damage. PKU testing is done on all newborns now. By avoiding phenylalanine, babies with PKU have normal brain development. The artificial sweetener in Diet Coke and the other products you mentioned has phenylalanine in it. It has no effect on you. You can drink these beverages without the slightest fear.

DEAR DR. DONOHUE: I have an enlarged prostate gland, controlled by medicine. I take the medicine at bedtime. At the same time, I place my partial dental plate in a cup with an Efferdent tablet. I often wonder what would happen if I swallowed the Efferdent tablet by mistake. Would it be life-threatening? — F.B.

ANSWER: I have a solution to your dilemma. Put your prostate medicine and your denture cleaner in two separate places. How about taking your medicine in the kitchen and placing your denture cleaner in the bathroom? Or if you want them both in the same place, cover your Efferdent glass after you put your plate in it.

Efferdent contains sodium perborate, ethylenediaminetetraacetic acid and potassium monopersulfate. Those chemical are irritants, and if ingested, they could cause neurological problems like headache and dizziness. I can’t believe that you would drink the whole glass of Efferdent by mistake. A sip might make your mouth uncomfortable, but it wouldn’t kill you. F.B., do you sit around thinking about things like this?

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.

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