Riverview Psychiatric Center

Psychology Articles by Dr. Arthur Dingley - Believing in Medicine

Dr. Art Dingley

How do medicines work? For starters, medicine must be absorbed into the body somehow. The rate of absorption may be helpful or problematic. Medicines which are inhaled or injected tend to act more rapidly because absorption is quicker. When medicines taken by injection must last for weeks or months, they are produced in “depot” forms which are gradually absorbed. Pills are coming out in “timed-release” forms, to slow down the absorption process. These may often be identified by a manufacturer’s suffix, such as CR, ER, XL, or XR.

Once medicine is absorbed, it gets distributed by the bloodstream. This means that parts of the body with less blood flow, such as cartilage, joints, and tendons, are hard to treat. Medicines must often be injected directly into those areas. Although the brain has a good blood supply, many medicines cannot get into the brain. We have a natural “barrier”, which is partly physical and partly chemical, to protect our brains against foreign molecules.

Once medicines are absorbed into the bloodstream, they pass, sooner or later, through the liver. Medicines taken by mouth and absorbed from the digestive tract pass through the liver before they reach their destination. Medicines which are inhaled or injected usually reach their destination before they pass through the liver. This matters because the liver is like a big grinding machine - it breaks molecules down into simpler forms which can either be used by the body, or eliminated. This explains one way in which drugs can “interact” with one another. One medicine may cause the liver to “speed up”. This will make other medicines less effective because the liver will degrade (metabolize) them more quickly. Or, one medicine may hog the liver’s ability to break down certain kinds of molecules. This will make other medicines more concentrated in the bloodstream.
Finally, medicines must be eliminated from the body. This usually happens when the molecule is carried by the bloodstream through the kidneys. As you might imagine, illnesses which affect the digestive tract, the liver, or the kidneys may interfere with the absorption, metabolism, and elimination of medicines. The dose may have to be adjusted.
Now, assuming we have a medicine which can be absorbed, taken up by the blood, reach a good concentration, withstand the “grinding” of the liver, and cross into the brain, how does that medicine change brain chemistry? Medicines attach to protein molecules on the surface of brain cells. The proteins are called receptors. The receptors normally interact with naturally-occurring substances in the nervous system. The drug is similar enough to the naturally-occurring substance that it can fit into the receptor like a key into a lock. When this happens, the receptor may be taken out of action for a while. Medicines which treat psychotic illnesses, for example, block receptors for a brain chemical called dopamine. On the other hand, some medicines bind to a receptor and cause it to bend. This sets off a chemical chain reaction inside the brain cell. Depending on the receptor, this chemical reaction may make the nerve cell more or less likely to “fire”. That explains why some medicines act, for example, as stimulants and others as sedatives.

One frequent concern is “side effects”. Side effects occur because most medicines do more than one thing. For example, some medicines bind to more than one type of receptor. Some antidepressants bind to serotonin receptors and to receptors which ramp down neuronal “firing.” Depression gets better, but the patient feels tired. Sometimes drugs cause side effects because the receptors to which they bind are found in several different organs. Some blood pressure medicines block adrenaline receptors found both in the heart and the lungs. Blood pressure may improve, but asthma may get worse. Multiple drug effects are not necessarily bad. A medicine that makes you less depressed and more tired is perfect if you also have trouble falling asleep.

Important as these biological facts may be, I have come to understand that beliefs and attitudes toward medicines are more apt to determine the outcome. For example, medicines are tested against inert compounds called “placebos”. When neither the patient nor the doctor know which group of people are getting the real drug, about a third of the placebo group gets better. The “placebo effect” is seen with every type of medicine for every ailment. There is no good explanation for it, except to say that, when people believe in the treatment, they get better. Disconcertingly, this is the same explanation usually given for the effectiveness of Voodoo.

Drug companies began capitalizing on patient beliefs years ago. The process of choosing a name for a new drug is surprisingly convoluted. Drug companies often hire a research firm to come up with a name people will like. The name of the new drug should convey something the company wants you to believe about the product. Market research shows that people believe a drug is more effective when its name includes Z and X. As a result, dozens of drugs have come to market with names which include those sounds or letters. You can probably think of several right now. Drug companies now spend more money advertising their wares to you than to me. TV ads for drugs use the same techniques proven to increase sales of all consumer products, particularly creating the belief that this item will improve your life. They also aim to reduce barriers to people asking their doctors about the “problem” and the treatment. Think Viagra.

Nationally, about one third of prescriptions written by doctors are never filled by the patient. There are many reasons for this. Some people are disorganized and lose the prescription. I have had patients lose a prescription between my office and the front desk. Some medicines are almost unbelievably expensive, even with insurance plans. Some people get “advice” from family and friends not to take a particular medicine because of something they “heard on TV”, and so forth.

However, I think the biggest reason for unfilled prescriptions is that many people don’t believe they need to take medicine. They politely accept a prescription but were secretly hoping for something else. Some people are hoping that their doctor will just listen and understand them. They interpret the offer of medicine as rejection. Some people want a particular drug and have no intention of taking anything else. If the prescription is for something else, they toss it. Some people feel coerced by family members into “getting on meds”. They fear that, by taking medicine, they are admitting that they are the problem and that everyone else in the family is excused.

Once people begin taking medicine, the effect (and side effects) are powerfully influenced by belief. Few people with serious psychotic illnesses, such as schizophrenia, continue taking medicines to control their symptoms for more than a few months. This has much more to do with lack of insight than actual side effects. People who believe that they are taking a “powerful psychiatric medicine” (whatever that is) are apt to believe that they are going to be sedated or (my favorite) “turned into a zombie”. Someone who believes that a psychotic disorder is worse than a mood disorder will believe that medicine for psychotic disorders must be somehow “stronger” than medicine for depression and have the potential for worse side effects. Some people believe that their medicine is “causing weight gain.” In fact, weight gain is only caused by eating too much food. There are no calories in medicines, but, when someone believes that his medicine is making him fat, the medicine goes.

Conversely, some people believe that their difficulties are all the result of a “chemical imbalance.” They want medicine and lots of it. If they don’t get better, and stay better, the problem is that their doctor has them on the wrong medicine or that the medicine “stopped working”. These people are apt to believe that they are powerless to improve their own lives or change their own behavior.

Medicine works, and fails to work, in many ways, for many reasons.

Next, we’ll take a look at the benefits, limits, and “ side effects” of psychotherapy.

Dr. Dingley is a psychiatrist at Evergreen Behavioral Services in Farmington. He may be contacted at adingley@fchn.org.

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