Drugs In The Elderly

Drugs In The Elderly, General Information

Pharmacokinetics is the study of how drugs work in the body. This relatively new medicine discipline examines the time required for drugs to be absorbed, how they are distributed in your body, how long they remain effective, and how they are eliminated.

Through the study of pharmacokinetics, we are coming to understand more about the interactions that determine specific drug effects and the individual diversity of different drug responses. Depending on several factors, including body weight, health, and age, we all respond to drugs differently.

One age group that is particularly sensitive to the actions of many drugs is the elderly. With age come changes in your digestive system that may alter absorption of drugs; in the functioning of your liver that can make it harder for your body to break down (metabolize) and eliminate certain drugs; in your circulatory and nervous systems that affect responsiveness to many drugs; and in mental functioning such that taking medicines according to instructions is more difficult.

Establishing Dosages and Monitoring Side Effects.

Because physical changes make older people more sensitive to drugs, the elderly generally require lower doses to achieve the desired effects and to avoid toxic overdoses. Unfortunately, the side effects of drugs, and the misuse and abuse of drugs, are distinctly more serious problems in the elderly: adverse reactions to medication occur frequently in our older population, and it is often more difficult for the elderly to eliminate their effects. It has been estimated that as many as one in four drugs administered to the elderly institutions may be ineffective or unneeded.

Compounding the problem, many elderly people use nonprescription drugs without the knowledge of their physician. In addition, many elderly people misuse drugs by taking less than the prescribed dosage in a misguided attempt to reduce costs.

Beware of Specific Drug Problems

Some drugs widely used by elderly people may present special concerns. Diuretic drugs are commonly used because they reduce the amount of water in the body, an effect that ultimately reduces the workload of the heart and arteries. These "water pills" increase the flow of urine and are used to treat hypertension, heart failure, and other ailments common to older people, but they can also cause a loss of potassium and other minerals from the body. A potassium deficiency will produce symptoms that range from weakness, listlessness, and a loss of appetite to an irregular heartbeat. A potassium deficiency can be resolved by reducing the dosage, changing the diuretic, or taking a potassium supplement. Many foods contain potassium, but it is difficult to increase the amount of dietary potassium by selecting certain foods. Generally, problems of potassium

depletion will require taking a potassium supplement to prevent or resolve the problem if you continue to take the same diuretic.

Many older people receive other anti-hypertension medications that may make them feel depressed, drowsy, or suddenly faint, especially when they try to stand up. The elderly are also more likely to experience adverse effects from sedatives and tranquilizers. Barbiturates are particularly risky because they can cause severe mental confusion or even psychosis if taken to excess. Benzodiazepine tranquilizers, taken to ease the

nervousness and stress of everyday life, may also cause drowsiness, shakiness, and confusion in older people. If it is necessary for you as an older person to take a tranquilizer, your physician will choose the drug carefully and probably will prescribe a dosage that is lower than what is normally indicated for a younger person.

Digitalis medicines, prescribed to improve the strength and efficiency of the heart, also can be a serious problem for older people. Older people sometimes develop symptoms of toxicity from these drugs, including excessive fatigue, loss of appetite, vision problems, and psychological disturbances. These symptoms occur in the elderly because they are

commonly given digitalis for longer periods and they do not eliminate the drug as readily as younger persons. Older people sometimes will receive lower doses of digitalis medications because, over time, the medicine can accumulate to toxic levels.

Beware of Mixing Drugs and Alcohol

In an effort to alleviate some of the age-related problems of loneliness and boredom that many elderly people face, some older people use drugs, such as alcohol, prescription drugs, and illegal (street) drugs. A National Institute of Drug Abuse survey indicated that two-thirds of all persons over the age of 65 use prescription drugs, and except for cardiovascular medications, the most commonly used drugs were sedatives and tranquilizers. More than half of all the persons using tranquilizers and sedatives said they could not perform their daily activities without these drugs. If you use sedatives or tranquilizers, take special care not to abuse them. The use of many drugs along with alcohol can cause harmful interactions.

Multiple Drug Use

Perhaps the most common form of drug misuse in the elderly is multiple drug use. This involves taking too many drugs or inappropriately taking drugs that interact with other.

Elderly persons often have numerous symptoms or illnesses. Sometimes there is a tendency for each new symptom to result in a visit to the physician and a new prescription, all too frequently without sufficient regard to the schedule of medicine already being taken. This pattern can lead one to take a surprising number of medicines, some of which may interact harmfully with each other.

Do not expect a medicine for every new symptom. Sometimes a symptom can be

resolved by reducing the dose of another medicine or reorganizing the schedule of medicine. Also, review the schedule of all your medicines with your physician on every visit (particularly if a medicine is added) to determine whether the schedule can be simplified. With multiple drug use, it is hardly surprising that in many instances a person can get confused and take too little or too much of one or more drugs or experience

unwanted side effects from drug interactions.

Older people often need assistance in following drug therapies, especially if they have multiple diseases that require the correct use of several medicines each day. When the drugs are not taken as prescribed, they may be ineffective; with the mixing of certain medications, negative drug interactions are far more likely and more severe.

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