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Introduction to Coping with Medication Side Effects
Medications are prescribed and taken precisely because they have certain desirable effects on the human body. The desirable reaction caused by a medication is known as the drug's activity, or therapeutic effect. But medications sometimes have undesirable effects as well. These unwanted effects are referred to as side effects, adverse reactions, or, in some rare cases, lethal effects.
Even if you experience minor side effects, it is very important that you continue to take your medication exactly as it was prescribed. You should take the full dose at the appropriate times throughout the day for the length of time prescribed by your doctor. It is simply not appropriate to take a lesser amount of medication to avoid side effects or because your condition appears to be improving. It is not valid to assume that taking half of the regular dose will provide half of the therapeutic effects. Indeed, a smaller dose may not provide any benefit whatsoever.
Some side effects are expected and unavoidable, but others may surprise the doctor as well as the patient. Such unexpected reactions may be due to an individual's particular response to the drug.
Side effects generally fall into one of two major categories -- those that are obvious and those that can be detected only through laboratory testing. Discussion between you and your doctor about your medication should not be limited to the most easily recognized side effects. Other, less obvious, side effects may also be harmful, and you should be sure you understand what they are.
If you know a particular side effect is expected from a specific drug, you can relax a little. Most expected side effects are temporary and need not cause alarm. You'll merely experience discomfort or inconvenience for a short time.
For example, you may become drowsy after taking an antihistamine or develop an upset stomach after taking the antibiotic erythromycin. Of course, if you find minor side effects especially bothersome, you should discuss them with your doctor, who may be able to prescribe another drug or at least assure you that the benefits of the drug you are taking far outweigh its side effects.
Sometimes side effects can be minimized or eliminated by changing your dosage schedule or taking the drug with meals. Be sure to consult your doctor or pharmacist if you have questions.
Some side effects signal a serious, perhaps even dangerous, problem. When a new medication is prescribed for you, you should ask your doctor what side effects might occur that would signal the need for immediate attention.
The following sections address obvious side effects, broken down by the body parts or systems affected by medication. The last section discusses those side effects that are more subtle or discernable only through laboratory testing. With subtle side effects, you may not be aware of any symptoms at all, or you may notice only slight ones. Therefore, your doctor may want you to have periodic laboratory tests or examinations to ensure that no subtle damage is occurring while you are on certain medications.
In the next section, let's start by reviewing the potential side effects to the circulatory system.
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Circulatory System Side Effects
Medication may slow down or speed up the heartbeat. If a drug slows the heartbeat, you may feel drowsy and tired or even dizzy. If a drug accelerates the heartbeat, you probably will experience palpitations (thumping in the chest). You may feel as though your heart is skipping a beat occasionally. For most people, these symptoms do not indicate a serious problem. If they occur frequently, however, consult your doctor, who may prescribe other medication or adjust your dosage.
Some drugs can cause edema (fluid retention), in which fluid from the blood collects outside the blood vessels. Ordinarily, edema is not a serious condition. But if you are steadily gaining weight or have gained more than three pounds within a week, be sure to consult your doctor.
Drugs may decrease or increase blood pressure. When blood pressure decreases, you may feel drowsy or tired; you may become dizzy, or may even faint, especially when you rise suddenly from a sitting or reclining position.
If a drug makes you dizzy or light-headed, sit or lie down for a while. To avoid light-headedness when you stand, contract and relax the muscles of your legs for a few moments before rising. Do this by pushing one foot against the floor while raising the other foot slightly, alternating feet so you are pumping your legs in a pedaling motion. Get up slowly, and be careful on stairs.
When blood pressure increases, you may feel dizzy, have a headache or blurred vision, hear a ringing or buzzing in your ears, or experience frequent nosebleeds. If these symptoms occur, contact your doctor.
Blurred vision is a common medication side effect, while hearing loss is an uncommon one. Read on to discover more about these and other potential side effects to ears and eyes.
Ear and Eye Side Effects
Vision or hearing loss can have a major affect on our everyday lives. Learn more about how medication can affect your eyes and ears.
Ears and Hearing
Although a few medications may cause loss of hearing if they are taken in large quantities, hearing loss is an uncommon drug side effect. Drugs that are used to treat problems of the ear may cause dizziness, and many medications produce tinnitus (a sensation of ringing, buzzing, thumping, or hollowness in the ears). Discuss any persistent hearing or ear problem with your doctor.
Eyes and Vision
Blurred vision is a common side effect of many drugs. Medications such as digoxin may cause you to see a halo around a lighted object, such as a television screen or a traffic light, and other drugs may cause night blindness.
Chlordiazepoxide and clidinium combination makes it difficult to judge distance accurately while driving and also makes the eyes sensitive to sunlight. While the effects caused by chlordiazepoxide and clidinium combination are to be expected, the effects on the eyes caused by digoxin are danger signs of toxicity.
In any case, if an eye-related problem occurs while you are taking medication, contact your physician.
Most medications have the potential to affect the gastrointestinal system in some way, whether it be diarrhea, dry mouth, or loss of appetite. Learn more about this in the next section.
Gastrointestinal System Side Effects
The gastrointestinal system includes the mouth, esophagus, stomach, small intestine, large intestine, and rectum. Almost any medication has the potential to cause a side effect involving some part of the gastrointestinal system. Many medications produce diarrhea, constipation, dry mouth, mouth sores, difficulty swallowing, heartburn, nausea, vomiting, loss of appetite, or abnormal cramping. Other drugs cause bloating and gas, and some cause rectal itching.
Diarrhea can be expected after taking many medications, but in most cases it is temporary and self-limiting; that is, the diarrhea should stop within three days. During this time, do not take any diarrhea remedy (even over-the-counter or herbal ones), and drink plenty of liquids to replace the fluid you are losing. If the diarrhea lasts more than three days or is accompanied by fever, call your doctor.
In some cases, diarrhea signals a problem. For example, some antibiotics can cause severe diarrhea. When diarrhea is severe -- it lasts more than three days or the stools contain blood, pus, or mucus -- the intestine may become ulcerated and begin to bleed. If severe diarrhea develops while you are taking an antibiotic or shortly after you complete a course of antibiotic therapy, contact your doctor.
As a side effect of drug use, constipation is more common but less serious than diarrhea. It occurs when a drug slows down the activity of the bowel. Medications such as amitriptyline and chlorpromazine have this effect.
Constipation also develops when drugs cause moisture to be absorbed from the bowel, resulting in a more solid stool. Constipation also may arise if a drug acts on the nervous system to decrease nerve impulses to the intestine -- an effect produced, for example, by methyldopa. Constipation caused by a drug can last for several days.
You may help relieve constipation by drinking eight to ten glasses of water a day, including more fiber in your diet, and getting plenty of exercise (unless your doctor directs you to do otherwise). Do not take laxatives unless your doctor directs you to do so. If constipation continues for more than three days, call your doctor.
Some medications can cause drowsiness or excitation. Turn to the next section to learn more about these and other potential side effects on the nervous system.
Nervous System Side Effects
Medications that act on the nervous system may cause drowsiness or stimulation (excitation).
If a medication causes drowsiness, you may become dizzy or your coordination may become impaired. If a drug causes stimulation, you may become nervous or have insomnia or tremors. Neither drowsiness nor stimulation is cause for concern for most people. When you are drowsy, however, you should be careful around machinery and should avoid driving.
Some medications cause throbbing headaches, and others produce a tingling sensation in the fingers or toes. If these symptoms don't disappear within a few days to a week, be sure to notify your doctor.
Shortness of breath is a characteristic side effect of some drugs, but it also may be a sign of a serious side effect. Read on to learn more about respiratory system side effects.
Respiratory System Side Effects
Side effects common to the respiratory system include stuffy nose, dry throat, shortness of breath, and slowed breathing. A stuffy nose and dry throat usually disappear several days after starting a medication.
If these side effects are bothersome, you may use nose drops (consult your doctor first) or throat lozenges, or you may gargle with warm salt water to relieve them. Shortness of breath is a characteristic side effect of some drugs (for example, propranolol). If you experience shortness of breath, check with your doctor. It may be a sign of a serious side effect.
Itching, swelling, and redness frequently indicate a drug allergy. Check out the next section to learn more about these and other potential side effects and what to do to relieve them.
If you experience any major side effects, contact your doctor immediately. Your dosage of the medication may need adjustment, you may have developed an allergy or sensitivity to the drug, or you simply may not be able to tolerate the particular medication well. Your doctor may therefore decide to discontinue the drug and possibly switch you to an alternative medication. However, never stop taking a prescribed medication unless you discuss it with your doctor first. |
Skin Side Effects
Skin reactions include itching, swelling, redness, rash, and sweating. Itching, swelling, redness, and rash frequently indicate a drug allergy. You should not continue to take a medication if you develop an allergy to it, but you need to contact your doctor before stopping the drug.
Some drugs increase sweating; others decrease it. Drugs that decrease sweating may cause problems during exercise or hot weather when your body needs to sweat to reduce body temperature.
If you have a minor skin reaction not diagnosed as an allergy, ask your pharmacist for advice on how best to manage the problem.
Another type of skin reaction is photosensitivity (also called phototoxicity or sun toxicity) -- that is, unusual sensitivity to sunlight. Tetracycline antibiotics can cause photosensitivity. If, while taking such a medication, you are exposed to the sun for even a brief period (10 or 15 minutes), you may get a severe sunburn. This doesn't mean you have to stay indoors while taking these drugs, but you should be fully clothed while outside and not remain in the sun too long. You should also use sunscreen on all exposed skin while in the sun -- ask your pharmacist to help you choose one -- and wear some type of head covering. Since medications may remain in your bloodstream after you stop taking them, you should continue to follow these precautions for several days after ending treatment with drugs that lead to photosensitivity.
We've covered all the major areas of the human body that are typically affected by obvious side effects. Now let's move on to the subtle side effects of medication in the next section.
Subtle Side Effects
As previously mentioned, subtle side effects are typically only discernable through laboratory tests or examinations. In fact, you may not be aware of any symptoms at all. Here are a few of the common areas that are subtly affected by medication.
Blood
Many drugs affect the blood and circulatory system but do not produce noticeable symptoms for some time. Some drugs decrease the number of red blood cells, the cells responsible for carrying oxygen and nutrients throughout the body.
If you have too few red blood cells, you become anemic; you appear pale and feel tired, weak, dizzy, and perhaps hungry. Other drugs may decrease the number of white blood cells, the cells responsible for combating infection. Having too few white blood cells increases susceptibility to infection and may prolong illness.
If a sore throat or a fever begins after you start taking a drug and continues for a few days, you may have an infection and too few white blood cells to fight it. Call your doctor.
Kidneys
If one of the side effects of a specific medication is to reduce the kidneys' ability to remove chemicals and other substances from the blood, then these substances begin to accumulate in body tissues. Over time, this accumulation may cause vague symptoms, such as swelling, fluid retention, nausea, headache, or weakness. Obvious symptoms, especially pain, are rare.
Liver
Since the liver is responsible for converting many medications and body chemicals into compounds that can be eliminated by other body organs (such as the kidneys, lungs, and gastrointestinal tract), drug-induced liver damage can result in a buildup of these substances. Because liver damage may be quite advanced before it produces any symptoms, periodic blood tests of liver function are recommended during therapy with certain medications.
As you can see, medication side effects range from minor, bothersome problems like skin irritation to major, potentially life-threatening conditions, such as liver damage. Because of this, be sure to discuss any side effects with your doctor.