Posts tagged Medication Side Effects
Trusting What Your Patients Tell You: Detecting Adverse Events in the Office Setting
Dec 30th
There are several published articles that have caught my attention that focus on perceived and self-reported adverse events in the patient population. One article, Adverse Drug Reactions in Elderly Patients as Contributing Factor for Hospital Admission: cross sectional study, Mannesse, C., et al, BMJ Vol 315, Oct. 1997. They reported that people were reliable in detecting adverse drug events in themselves, with a correct opinion in 73 out of 93 who answered the question whether they were experiencing an adverse drug event (ADE). However, these were adverse events that were less severe, and the more serious adverse events that caused hospitalization, such as gastrointestinal bleeding, were not well detected. In another study, Patient-reported Medication Symptoms in Primary Care, Weingart, S, MD, et al, ArchIntMed, Vol 165, Jan. 24, 2005, the authors measured how many people thought they were experiencing an adverse event (179 people & 286 events) and what percentage reported them to their physicians, along with what percentage were acted upon by their physicians. Only 69% were reported to their physicians, and only 76% were acted upon. The authors estimated that a failure to report symptoms led to 19 (21%) ameliorable ADEs, and 2(2%) preventable. A failure to change therapy in 48 cases led to 31 (65%) ADEs that authors estimated to be ameliorable. The conclusion is that people are fairly good at knowing when they are experiencing and ADE, a lesson I learned early on in working with older adults in a retirement community, where an older adult convinced me he was experiencing memory loss from one of his medications, but I didn’t believe him at first. So if we listen and believe, kind of like having faith, we should be able to detect an ADE before it affects the function of the older adult. We just need to ask the question.
In a study in progress, we performed comprehensive medication reviews (CMRs) in 69 older adults and within the CMR questionnaire we asked the two questions, 1) What history do you have of adverse drug events (medication side-effects)?, and 2) Do you think you are experiencing an adverse drug event right now? Of the 69 participants, 28 answered both questions positive, yet only 4 said they were having an ADE but had a negative history of an ADE. When applying a 2×2 contingency table with Fischer’s test for exactness, we found a p-value of 0.00001 meaning the correlation was highly significant. That is to say, people were far more likely to say they are experiencing an ADE if they had a history of an ADE, as opposed to those without a history. This aligns with another article titled Adverse Drug Reaction Risk factors in Older Populations, Hajjar, E., Hanlon, JT, et al, AmJGerPharm., Dec. 2003 Vol. 1 (2) 82-89. Risk factors for ADEs were developed by a panel of experts in ADEs and one risk factor identified and agreed upon by the experts was a history of an ADE.
So it stands that it might be wise to put in your office visit routine the questions of “What history of adverse effects do you have from medications?” and “Do you think you are experiencing an adverse effect right now?”, and then listen and act. You might positively affect the life of an older adult by keeping them more functional and/or out of the hospital.
Dizziness from Blood Pressure Medications
Aug 8th
JH was frequently dizzy when he stood up and had several falls as a result. We identified terazosin as a high-risk drug that frequently causes dizziness upon standing. His terazosin 10mg daily was changed to lisinopril and his dizziness and falls resolved.
What is described above is called orthostatic hypotension. It is best described as dizziness upon standing up from a seated or lying down position which can compromise blood flow to the brain thereby causing dizziness. This is a leading cause of falling in older adults but can be easily remedied. When blood pressure is affected by medications used to treat a cardiovascular condition such as high blood pressure there is an increased risk of experiencing this syndrome. Although many medications can cause dizziness by different mechanisms, we will focus on those that affect blood pressure.
Any blood pressure medication can cause a drop in blood pressure and isn’t this what we’re looking for? However, sometimes the medication dose is too high or perhaps another medication was added that interacted with the blood pressure medication thereby increasing its effect and risk of side-effects. In any event, whenever dizziness appears in someone who is taking a blood pressure medication orthostatic hypotension needs to be ruled out. Keep in mind that there are other non-drug causes of orthostatic hypotension in older adults and that’s why you should consult your physician. However, here’s a little information on how to determine if you are experiencing orthostatic hypotension.
Orthostatic hypotension can be measured by the nurse, physician or other trained health care professional. It is defined as follows:
Systolic (upper number) blood pressure decrease >20mmHg after standing for 2 minutes as compared to blood pressure when sitting,
AND/OR
Diastolic (lower number) blood pressure decrease >10mmHg after standing for 2 minutes as compared to blood pressure when sitting,
AND/OR
Increase in pulse >20 beats per minute,
AND
having symptoms of dizziness.
In general, if your blood pressure is LESS than 120/80 while on medications OR if you experience dizziness upon standing up, you should talk with your physician and have your medications reviewed for possible dose reductions or other medication changes in order to prevent a fall from dangerously low blood pressure.
Eye Drops: Systemic Side-Effects
May 6th
The use of timolol eye drops in people with glaucoma is the leading risk factor for falling. PB had her timolol changed to another drug and her balance improved within 3 days and she stopped using a walker after 7 days.
Adverse Medication Events: The significance of eye drops causing side-effects in older adults
Adverse drug events (ADE’s), also called side-effects, are responsible for 2.2 million hospital visits and 106,000 deaths each year! If ADE’s were a disease by itself, it would be the 5th leading cause of death by disease. This becomes more likely as we age since we are more sensitive to the effects of most medications and we tend to take more medications.
The most recent information we have is in relation to systemic side-effects from eye drops. One might assume that the effects of a topically applied eye drop would be limited to the area of the eye. However, the transit of medication through the tear duct into the body make many eye medications as potent as an intravenous (injected) dose of medication. Here are a couple ways to put this into perspective:
**One (1) drop of Timolol 0.5% Opthalmic Solution is as strong as one (1) 10 mg oral tablet used for treatment of hypertension or angina.
**The leading risk for falls in patients with glaucoma is the topical administration of (Timoptic) timolol eye drops.
Here are some examples of documented side-effects found in the literature:
1) Bronchospasm and congestive heart failure (Timolol)
2) Depression (Timolol & other beta blockers)
3) Low blood pressure (Timolol & Pilocarpine)
4) Headache or “brow ache” (Pilocarpine)
5) Urinary frequency (Pilocarpine)
6) Asthenia (Alphagan) Asthenia is defined as physical weakness and loss of strength
This is only mentioning side-effects from one drug at a time. Many older adults take up to four eye drops at the same time for their glaucoma. That being said, we need to pay closer attention to what’s going on. Here’s what we recommend:
1) One way to reduce the drug from being absorbed into the body is to follow a particular technique. This procedure is called the “double DOT” procedure” which stands for “Don’t open eyes technique and Digital Occlusion of the Tear Duct” This involves closing the eye and applying pressure over the lacrimal duct (tear duct) for 1-2 minutes after application of the eye drop. This technique reduces systemic absorption by two-thirds.
2) Describe what you might think are side-effects from the list mentioned above.
3) Report those to the prescriber of those medications and/or consult your pharmacist. You may also consult Elder Drugs if you have concerns relating to your eye drops.
BEWARE! Drugs That May Cause Harm
Jan 31st
Not all medications that are commonly used are ideal for older adults. In fact, there is a list of medications that may actually pose as hazardous for use in older adults. This list, called the Beer’s List, has several medications that can send older adults to the hospital or cause cognitive or functional impairment. This article reviews a few of those drugs while adding a few more we know to be of concern when used in older adults. If you would like any references that support our findings, please write us and we can forward those to you.
NITROFURANTOIN
This drug is commonly used to either treat or prevent urinary tract infections. The problem with this drug is three-fold: 1) In many older adults it does not get into the bladder due to reduced kidney function, which is common in aging, so it may be ineffective, 2) use can cause peripheral neuropathy, or damage to the nerves, and 3) it can lead to hypersensitivity reactions of the lungs, called pulmonary fibrosis.
To determine if this drug is appropriate for an older adult, a consulting pharmacisst can estimate your kidney function. If it is below a threshold then your physician may need to be made aware that alternative approaches may be best. Although this medication can work for some individuals it’s use should be monitored closely.
DIGOXIN
This medication can be very useful in those with abnormal heart rhythms, especially atrial fibrillation, although newer therapies now are preferred as first-line choices. Due to reduced kidney function in older adults, this drug can accumulate and lead to toxicity which can be fatal. We don’t intend to scare you because your physician should be monitoring for potential toxicity and monitoring its use greatly reduces the risk of this adverse effect, but one should always be aware of the potential risks of its use. A factor that contributes to toxicity is low serum potassium, which your physician should also monitor while on this drug. Digoxin is one of the top three drugs that causes serious adverse effects that lead to hospitalization.
AMIODARONE
This is another medication that can be quite useful in controlling atrial fibrillation but can be toxic. It can cause hypothyroidism, lead to vision loss and perhaps pulmonary fibrosis. There have been several case reports of amiodarone-induced confusion. We advise you are aware of the potential adverse effects of this drug and work with your physician to ensure you have a monitoring plan. Amiodarone can also interact with warfarin (Coumadin) and enhance the effects of warfarin. Your physician should also have a monitoring plan to guard against any adverse effect from combination therapy.
METFORMIN
Although quite safe in a large number of older adults, this drug can accumulate in those with reduced kidney function. The rate at which this leads to serious adverse effects is quite low, but when it does it can be very serious. As mentioned above, your kidney function can be estimated and, along with your total daily dose and age, we can give guidance as to whether you are at high risk for adverse effects from this drug. What can happen, although rare, is a condition can develop called lactic acidosis, which can be fatal.
PROPOXYPHENE
This narcotic analgesic has no better effect than acetaminophen (Tylenol) at maximum dose yet comes with all the narcotic-related side-effects, such as sedation, impaired cognition, constipation which can worsen urinary incontinence, among others. If you are finding this drug relieves pain and you are functioning well, then perhaps this is not an issue. However, if you still experience pain or think the drug may be causing side-effects, you may want to learn more about how to effectively and safely manage your pain. NOTE: Propoxyphene was withdrawn from the U.S. market in 2010 by the FDA and is no longer available.
DIPHENHYDRAMINE (BENADRYL, TYLENOL PM)
This drug is widely used in older adults primarily because it’s available without a prescription. It comes in many over-the-counter (OTC) formulations so one must read labels carefully and not go by the marketing of the product that may imply the drug is safe. This drug can cause cognitive impairment and lead to falls. It is known to affect function and increase the length of hospital stays. Clearly, it is not a drug older adults should rely on. If you have problems sleeping we suggest you learn more about how to sleep better and not rely upon this medication since it’s effects are short lived yet it’s toxicity lingers. This drug is commonly used in OTC sleep aids.
NON-STEROIDAL ANTI-INFLAMMATORY DRUGS- Commonly used drugs for joint pain, headache and body aches that are even available without a prescription include Motrin (ibuprofen), Aleve (naproxen) and aspirin among others. These drugs are not necessarily safe just because you can buy them Over-The-Counter. In fact, indiscriminate use of NSAIDS is a leading cause of hospitalization and death from gastrointestinal bleeding and one of the top adverse drug events (ADE’s) that we focus on preventing. It is now understood that older adults are at higher risk for a GI bleed because of certain risk factors but also because of certain medications they take on top of the NSAID’s. Drugs like warfarin and ibuprofen in combination greatly increase the risk of a GI bleed in an older adult. Now that we understand how high this risk is it is recommended to approach pain management in older adults much differently. If pain is chronic and disabling, the use of low-dose opiates is now recommended by the American Geriatrics Society in order to reduce the risk of a serious ADE from an NSAID. There are other side-effects from this class of drugs that are beyond the scope of this article. If you have a specific question feel free to use the Ask A Pharmacist feature on this web site.
CIMETIDINE
This medication, brand name Tagamet, is available over-the-counter and used for heartburn. It was originally available as a prescription for the treatment of stomach ulcers. It has the ability to cause cognitive impairment and, in certain circumstances it can cause delirium. Drugs that are more favorable but accomplish the same task are Pepcid and Zantac.
METOCLOPRAMIDE
This medication is used to promote gastrointestinal motility. It is used in people with diabetes and other conditions in which the nervous system does not function well and the stomach does not empty it’s contents soon enough thereby leading to nausea. The problem with this drug is that it can cause movement disorders just like Parkinsonism, which is manifest by tremors and slowed movement. Long term use is associated with a possibly irreversible movement disorder called tardive dyskinesia. This condition is manifest by by uncontrollable movements of the face and limbs which can impair one’s ability to function. If this medication is absolutely needed it should be used at the lowest dose possible and the user should be screened for tardive dyskinesia at least annually.
DETROL & DITROPAN (BLADDER HEALTH DRUGS)
Urinary incontinence is a prevalent condition in many American’s but what many people don’t know is that non-drug methods can be very effective at managing the condition. That would be good to now since these medications are shown to cause older adults to function more slowly and impair cognition. One study showed that participants taking one of these drugs functioned as if they were 78 or 79 years old and not as if they were 75 years old as in the control group. The management of incontinence should include comprehensive evaluation first, then only medications when non-drug methods have not achieved the goal.
AMITRIPTYLINE & IMIPRAMINE (TCA’S)
These older antidepressants are still used for neuropathic pain but can cause significant anticholinergic side-effects, such as dry mouth, constipation , dizziness, sedation and memory impairment. Newer antidepressants are by far preferred as first line agents in the treatment of depression in older adults.
DIAZEPAM & FLUAZEPAM (BENZODIAZEPINE’S)
These drugs are so well documented to cause falls and fractures that Medicare refuses to pay for them under Part D! Now that’s strong evidence to re-think taking a drug such as diazepam, lorazepan or alprazolam, and others that are related. They are also responsible for causing confusion and delirium. If one of these drugs is needed it should be used at the lowest dose for the shortest period of time.
