Drug-Induced Diseases: Part 2

This is the second installment in a two-part article about drug-induced diseases, the first of which was published in last month’s edition of Worst Pills, Best Pills News. Full names of individuals are not used to protect the identities of those involved.

Specific examples of patients with drug-induced diseases

Woman homebound due to misprescribed heart drug
54-year old woman named Liz was prescribed the heart drug amiodarone (CORDARONE) to treat a common heart condition. She was not told that the drug was not approved by the Food and Drug Administration (FDA) for her condition. The pharmacy leaflet mentioned nausea and dizziness as side effects, but not lung toxicity. She is now dependent on an oxygen tank to breathe and does not have the strength to leave her house.

Man develops parkinsonism from antipsychotics prescribed for irritable bowel syndrome
Larry was an otherwise healthy 58-year-old man with diarrhea believed to be due to “irritable bowel syndrome.” He was given trifluoperazine (STELAZINE), a powerful antipsychotic, to “calm down” his intestinal tract. STELAZINE is not even approved for treating such medical problems. Six months after starting STELAZINE, Larry developed severe parkinsonism, a neurological condition characterized by tremors, limited movements, rigidity and postural instability. To correct this, Larry was started on L-dopa (also known as levodopa), a drug to treat Parkinson’s disease. Presumably, the doctor did not realize the parkinsonism was drug-induced, and the STELAZINE was continued. For seven years, Larry took both drugs until finally seeing a Parkinson’s specialist. The specialist recognized the real cause of his problem, stopped the STELAZINE, and slowly withdrew the L-dopa over a six-month period. Larry’s severe, disabling parkinsonism cleared completely.

The same Parkinson’s specialist who “cured” Larry of his drug-induced parkinsonism saw, in just three years, 38 other patients with drug-induced parkinsonism and 28 with drug-induced tardive dyskinesia, a syndrome of involuntary movements.

None of these patients were psychotic, the one condition for which antipsychotic medications are approved. Rather, the most common reasons for using the parkinsonism-inducing drugs were chronic anxiety and gastrointestinal complaints. The most frequent culprit (in 19 of these 39 patients) was REGLAN, usually prescribed for heartburn or for nausea and vomiting. Doctors often prescribe REGLAN before trying other more conservative and safer methods. Other drugs that brought on parkinsonism included prochlorperazine (COMPAZINE), haloperidol (HALDOL) and chlorpromazine (THORAZINE).

Confusion and hallucinations caused by ulcer drugs
Leticia wrote to Public Citizen about her 80-year-old father, saying that she had to repeatedly ask his doctor about the possible role of her dad’s ulcer drugs in causing confusion and hallucinations before the doctor listened. Her father had tried three different drugs – cimetidine (TAGAMET), ranitidine (ZANTAC) and famotidine (PEPCID) – for his ulcers, and each had caused these side effects. When the doctor finally switched Leticia’s father to an antacid – aluminum hydroxide and magnesium hydroxide (MAALOX) – his mind completely cleared and he was his old self, no longer confused or hallucinating.

Woman develops reversible mental impairment from tranquilizer
The first time 79-year-old Sally saw her physician son-in-law after several months, he noted that she had suffered severe impairment of her otherwise sharp mind. She was acting confused and, for the first time in her life, was unable to balance her checkbook. When he questioned her, she was able to remember that her problem had started around the time she was put on the tranquilizer lorazepam (ATIVAN). After this link was discovered, the drug was slowly discontinued and the mental impairment disappeared.

Man has auto accident after one dose of tranquilizer
Ben, a 64-year-old, was scheduled to have a biopsy done at a local hospital one morning. The doctor gave him a free sample of a tranquilizer, alprazolam (XANAX), to take an hour or so before the procedure so that he would be relaxed for the biopsy. Ben was not told that he should not use the drug if he was going to drive. While driving to the hospital for the biopsy, he blacked out. The car went over a fence and sustained $6,000 worth of damage, but fortunately Ben was unhurt.

Dangerously slow heart rate with propranolol use in the elderly
Shara, a 60-year-old assistant at a senior citizens’ center, was started on propranolol (INDERAL, INDERAL LA) to treat her high blood pressure. Unfortunately, her doctor did not realize that the dose of this sometimes useful drug must be reduced in older adults, and the dose she was prescribed was too high for her. Two days after she started taking the drug, she began feeling very weak. The side effect was so bad that by the third day on the drug, she went to a hospital emergency room, where her pulse rate was found to be 36 beats per minute. This dangerously low rate fully explained her weakness. The drug was stopped, and Shara’s heart rate returned to normal. Later a low dose of a different drug was prescribed and produced no side effects.

Child dies from drug prescribed for attention deficit hyperactivity disorder
Jamal, a bright 7-year-old boy, was prescribed an antidepressant, imipramine (TOFRANIL), to treat attention deficit hyperactivity disorder. His parents were not provided with complete, accurate information about the drug. As a result, they were unaware that the drug can cause life-threatening heartbeat irregularities (called arrhythmias), that the dose prescribed to Jamal was too high and that the tremor and convulsions that Jamal began to have were actually side effects from the TOFRANIL. Treatment with the drug was continued, and one day, while at school, he collapsed and died of an arrhythmia. If his parents had been adequately warned about this drug, Jamal might still be alive today.

Poor prescribing is often the cause of symptoms

The World Health Organization, in discussing the problem of side effects in the elderly, has stated some principles applicable to people of all ages:

Quite often, the history and clinical examination of patients with side effects reveal that no valid indication [purpose] for the offending drug has been present ... Adverse reactions can to a large extent be avoided in the elderly by choosing safe and effective drugs and applying sound therapeutic principles in prescribing, such as starting with a small dose, observing the patient frequently, and avoiding excessive polypharmacy [the use of multiple drugs at the same time].

In other words, patients who suffer adverse drug reactions are very often victims of drugs that they should not have been taking that way in the first place.

A 1992 study published in Medical Care examined prescriptions given to people being discharged from a community hospital. It focused on those who were prescribed three or more drugs to treat chronic illnesses. The results of this study are quite disturbing, both in what they say about the doctors’ prescribing practices and as evidence of the potential damage that these prescribing practices can do to older adults. Of the 236 people intensively studied:

• 81 percent had one or more prescribing problems with the prescriptions they were given, including inappropriate drugs, doses or schedule;
• 60 percent had been given one or more prescriptions for a drug that was an inappropriate choice of therapy because it was either “less than optimal medication given the patient’s diagnosis” or there was no established indication for it;
• 50 percent were given either too high or too low a dose of the drug;
• 44 percent of the patients were given a combination of drugs that can result in harmful drug interactions;
• 20 percent were given drugs that unnecessarily duplicated the therapeutic effect of another drug they were taking.

Fortunately, a consultant pharmacist involved in the care of more than half of the people was able to reduce the risks to the patients by making recommendations to the prescribing physicians.

Complete lists of the most common drug-induced side effects along with the drugs that can cause them are available free of charge on www.WorstPills.org. In the box that accompanies this article are some of the symptoms that are also frequently caused by drugs. They are the kinds of problems that you or many doctors might instead first attribute simply to “growing old” or “getting nervous.” To see the complete list, go to www.worstpills.org/public/page.cfm?op_id=5#summary.

Although some of these adverse effects occur most commonly in older adults, all of them have also been documented in younger people, although sometimes not as often.