A man walks out of the clinic, where he just had a routine colonoscopy. “The doctor says I’m fine,” he tells his wife who is waiting in the car. “He doesn’t need to see me for another five years.”
“Wonderful!” she says. “Did it hurt?”
“Ummm, well…” he stammers. “Actually, I don’t know. I don’t remember a thing about it. It’s weird—I can’t remember anything.”
The reason he doesn’t remember is that his doctors slipped him a dose of a drug that wiped out his memory of the event. Called midazolam and marketed under the brand name Versed (pronounced ver-SEDD), the drug is routinely used after minor surgical procedures. The colonoscopy could have been smooth as silk or excruciatingly uncomfortable—the medical team could have danced on the table and sung “Auld Lang Syne”—and the patient, who had been wide awake the whole time, would not remember one jot of it. While patients might well object to the idea of being given a drug to wipe out their memory banks, the practice is as routine as hand-washing.
I once asked a colonoscopy nurse why they always used Versed. “So patients will come back,” she said. If patients remembered every last discomfort and indignity of the procedure, they would be a lot less eager for their next exam. Some anesthesiologists use propofol (marketed as Diprivan) rather than Versed. Propofol was the drug that, in combination with other drugs, was implicated in Michael Jackson’s death. It causes a similar amnesia.
Versed is an extreme illustration of an important fact: Drugs can wreak havoc with your memory. Versed is in the same chemical class as Valium, Ativan, and Xanax—all of which are commonly used for anxiety. They can all affect memory, albeit not so decisively as Versed.
And so can many other medications. Even common cholesterol-lowering drugs, including Lipitor and Crestor, can cause memory deficits that mimic early Alzheimer’s disease. You discover the truth only when you stop the medication and find that your memory gradually returns.
But there is an even more fundamental point: All kinds of things can affect your memory. A great many medical conditions can cloud your thinking. As words start escaping you and you start to feel less and less like yourself, there may well be a simple reason that can be identified and fixed.
In this chapter, we’ll look at the conditions that can harm your memory and what you can do about them.
When anyone experiences any sort of memory problem, medications should be high on the list of suspects. Unfortunately, many people, including many doctors, do not think to look there until problems have carried on too long. Below we will look at specific medications that interfere with memory or cause other cognitive problems. But first, a few important points:
• Medication effects add up. The effects of one medication can add to those of another. For example, you might be taking an antidepressant that blocks a brain chemical called acetylcholine. Aside from a little dry mouth or constipation, the side effects are not too bad. But then later on you might need an allergy medicine, and it blocks acetylcholine, too. With two drugs blocking the same brain chemical, their side effects add up, and it can be too much for the brain, clouding your thinking and interfering with memory. A common scenario is that one doctor prescribes a medication. Then another doctor prescribes a second medicine for an unrelated condition. More and more drugs are added, but none of the doctors look at the full list of pharmaceuticals marinating the patient’s brain. Medicines, of course, are very useful and sometimes lifesaving. But it is important to step back from time to time and take a fresh look at what you are taking.
• Drugs can interact with food. If you were to sip a grapefruit juice, you probably wouldn’t imagine that it could disable the enzymes your liver uses to break down Versed and Lipitor. But it does, and that means the drugs stay in your blood much longer, heightening their assault on your memory. Grapefruit juice has a similar effect for many other medicines, too, typically lasting for about twenty-four hours after your last glass of juice.
• Talk with your doctor—now. If you suspect that medications may be causing a problem, speak with your doctor. It is often possible to discontinue one or more medications to see if memory improves. However, the safety of taking a “medication vacation” and how to go about it differ from medicine to medicine. For example, there is little risk to stopping a cholesterol-lowering drug such as atorvastatin (Lipitor) for a few months, but stopping a blood pressure medication could lead to a prompt and dangerous increase in your blood pressure. Ditto for diabetes medicines; stopping them could mean a risky spike in your blood sugar. You do not want to stop them on your own. Also, stopping some medications can lead to withdrawal symptoms. Anxiety medications, for example, can be habituating, and it can be dangerous to stop them abruptly. The answer, in every case, is to speak with your doctor before making any changes in your medications.
• Keep a list. It pays to keep a list of any medications you are taking. Update it regularly, and give a copy to any doctor you happen to consult. Include the drug name, size of each pill (milligrams), what time of day you take it, and the number of pills you take each time. This will make your doctor’s job easy and will help prevent mistakes.
Here are the most common culprits—medications that are known to cause cognitive problems. This does not mean that they always cause problems—for some medications, memory problems are quite uncommon—or that they can be blamed for cognitive problems in any given person. But when you are looking for answers, these medications should be on your list of suspects.
Cholesterol-lowering drugs. Cholesterol-lowering drugs are among the most commonly prescribed medications. With well over $10 billion in annual sales, Lipitor was the world’s leading pharmaceutical moneymaker before going generic in 2011.
Lipitor is a statin, the group that also includes Crestor, Mevacor, Zocor, and many others. Generally, their safety profile is good. In fact, lowering cholesterol is one way to reduce the risk of Alzheimer’s disease and stroke. Because statins are so widely prescribed, many people imagine they are innocuous. Some doctors refer to Lipitor as “vitamin L,” and some have even suggested it be sold without a prescription, like aspirin or vitamins.
However, statins do have side effects, some of which are serious. They can cause muscle and liver toxicity and, in high doses, are linked to diabetes.1 And a number of people have reported striking effects on their memory: confusion, disorientation, and memory gaps that look like the beginnings of Alzheimer’s disease.
Duane Graveline is a physician and a former NASA astronaut who lives near the Kennedy Space Center on Florida’s Atlantic coast. Returning home from a walk one day, he felt totally disoriented. He had no idea where he was. A woman came out to greet him, and he did not recognize her. This was his wife, who saw that something was very wrong with Duane. His memory banks had been wiped out. Later on in the hospital emergency room, he tried to piece things together. The only explanation he could think of for his bizarre amnesia was the Lipitor he had started several weeks earlier. Stopping the medicine cured his memory loss.
But later on, he restarted Lipitor at half the dose, only to find that, after about six weeks, it scuttled his memory again, erasing everything after high school, including his wife, children, and everyone else. He looked into the effects of statins on memory and ended up dedicating several books (The Dark Side of Statins and Statin Drugs: Side Effects and the Misguided War on Cholesterol, among others) and a website (www.SpaceDoc.com) to getting the word out.
At the University of California at San Diego, Beatrice Golomb documented 171 cases of people who reported significant cognitive problems while taking statins.2 In 90 percent of cases, stopping the drug fixed the problem, often within days. Some of these people had been mistakenly diagnosed with Alzheimer’s disease—diagnoses that no longer applied. Some later resumed taking statins—sometimes several times—only to find their symptoms returning each time. The higher the dose, the more likely they were to have problems, and some people have not fully recovered, even years after stopping the medication.
The side effect seems to be uncommon. But with so many people taking statins, even rare side effects mount up. And doctors treating older people may mistakenly assume that their symptoms are age-related or are attributable to Alzheimer’s disease, and may never stop the drug to see if things clear up.
Luckily, there are other ways to lower your cholesterol, as we saw in chapter 3. A chicken-and-fish diet is not very effective, but when people set aside animal products and greasy foods altogether, the effect on their cholesterol levels can be so dramatic that medications are usually unnecessary.
Brand names are in parentheses:
atorvastatin (Lipitor)
ezetimibe/simvastatin (Vytorin)
fluvastatin (Lescol)
lovastatin (Mevacor)
pravastatin (Pravachol)
rosuvastatin (Crestor)
simvastatin (Zocor)
Sleep medications. In the preceding chapter I mentioned the surprising memory problems that can come from sleeping pills. I strongly suggest avoiding sleeping medications, if possible, and using the more natural approaches to sleep that I described. Common sleeping medications that can interfere with memory include:
diphenhydramine (Benadryl, Sominex)
doxylamine (Unisom, NyQuil, Alka-Seltzer Plus Night Cold, Tylenol Flu Nighttime)
zolpidem (Ambien)
Antidepressants. Antidepressants work by changing the balance of neurotransmitters that control moods. Some also block acetylcholine, so confusion and memory problems can occasionally occur.
Antidepressants for which memory effects have been commonly reported are listed below.
amitriptyline (Elavil)
desipramine (Norpramin)
imipramine (Tofranil)
nortriptyline (Pamelor)
venlafaxine (Effexor)
Keep in mind, however, that any antidepressant can be considered a possible contributor to confusion or memory problems. Even antidepressants that have little or no effect on acetylcholine—fluoxetine (Prozac) and paroxetine (Paxil), for example—should be considered suspects if clouded thinking or memory problems arise.
Many people are tackling depression by other means altogether, often with spectacular results. New psychotherapy methods are much quicker than previous treatments and work very well. Exercise has also been shown to lift moods, perhaps as well as antidepressant drugs. Of course, if you’re depressed, you may not feel like exercising—or doing much of anything—but once you start, you find that you get an energy boost, and the noticeable payoff keeps you going.
Antihistamines. Many allergy pills block acetylcholine, the neurotransmitter mentioned above. With occasional use, this is not likely to be a problem, but if you take these medications over extended periods or take more than one medication with this same action, side effects are more likely. Common antihistamines in this category include:
brompheniramine (such as Dimetapp)
chlorpheniramine (such as Chlor-Trimeton)
clemastine (such as Tavist)
diphenhydramine (such as Benadryl)
Newer antihistamines, such as fexofenadine (Allegra) and cetirizine (Zyrtec), are less likely to have these undesirable effects.
Anxiety medications. Valium, Ativan, Xanax, and other popular anxiety medications are in the same chemical class as Versed, the operating-room drug I mentioned at the beginning of this chapter. They do not have anywhere near its power to erase memories. But they can nonetheless impair your memory and blunt your emotions.
It is important to be aware that anxiety drugs are clumsy. When they reach into your brain, they do more than simply turn down the anxiety button. They bump into many different parts of the brain and adjust brain chemistry in myriad ways, not all of which are helpful.
One more problem: With prolonged use, you can become physically dependent on anxiety drugs, as I mentioned above. This does not mean that you will end up in a back alley buying your next dose, but it does mean that stopping them abruptly can lead to rebound anxiety and even seizures. To prevent this, your doctor will taper you off gradually.
alprazolam (Xanax)
clonazepam (Klonopin)
diazepam (Valium)
lorazepam (Ativan)
oxazepam (Serax)
temazepam (Restoril)
triazolam (Halcion)
Painkillers. Many people take analgesics on a daily basis for chronic pain. Opiate pain relievers (such as morphine, oxycodone, and hydrocodone) can interfere with your memory over the short term, although most people who take them on a more ongoing basis for chronic pain seem to habituate to their effects and do not have serious cognitive problems.3 Even so, if you are on painkillers and having memory problems, it is worth speaking to your physician about alternatives to your current medications.
If you are using pain medications for rheumatoid arthritis, migraines, or fibromyalgia, let me encourage you to see if a dietary approach might help. Many people find that these painful conditions are triggered by specific foods, such as dairy products, eggs, white potatoes, and a short list of others. In a previous book, Foods That Fight Pain, I detailed a simple way to sort out whether eliminating one or more of these foods can cure your problem.
Do not take this on faith. You might simply give it a try and see for yourself. Not everyone finds a food trigger, but when you do, a diet adjustment can allow you to reduce or eliminate your need for medication.
Blood pressure medicines. Blood pressure medicines have been shown to affect memory in rare cases. Propranolol is sometimes used to reduce blood pressure and more often to slow a rapid heart beat (tachycardia). It can affect the brain.
However, high blood pressure is dangerous and is a key contributor to stroke risk. So if you are on a blood pressure medication, be sure to speak with your doctor before changing the dose.
At the same time, do not neglect nondrug methods that can improve your blood pressure. Weight loss, limiting sodium, following a plant-based diet, and exercise can go a long way toward eliminating the need for blood pressure drugs. See chapter 4 for more details on how diet changes can help.
Acid blockers. Many people use medications to block the production of stomach acid. Ranitidine (Zantac) and cimetidine (Tagamet) have been reported to cause confusion in rare cases. Luckily, the problem disappears when the medication is stopped.
The medicines listed above are the common offenders. But other drugs could affect memory, too, and new ones enter the market every year. Often their full range of side effects does not become clear for several years.
The problem is likely to get worse before it gets better. In recent years, drugmakers have realized that they do not make much money from medicines that are used for just a few days or weeks at a time, such as antibiotics. So they are investing heavily in medicines that are used essentially for life. Cholesterol drugs, diabetes drugs, blood pressure drugs, and arthritis drugs are the pharmaceutical industry’s little golden eggs.
The Food and Drug Administration does not require Lipitor’s manufacturer to disclose to patients that many of them would not need the drug at all if they were to follow a plant-based diet. Nor does it require manufacturers of diabetes or blood pressure medicines to reveal that similar menu changes would reduce the need for those drugs, too. On the contrary, drug companies spend a fortune “educating” us about the essential nature of their products. Their continuing medical education courses for doctors, grants to medical centers, and prime-time television advertisements are all designed to help us forget that many of our most common medical problems have their roots in diet and lifestyle.
So do take advantage of the benefits of medicines when you need them. But be cautious, and always be alert to the possibility of side effects, especially if the number of medications you take increases.
If you are experiencing memory problems, you will want to speak with your doctor about possible hidden causes. Here are some important ones to consider:
Could your choice of bread affect your brain? If you’re gluten intolerant, it could. Gluten is a protein found in wheat, barley, and rye. For most people, it is easy to digest and is healthful and nutritious. But about 1 percent of people have a hereditary condition called celiac disease. If you are one of them, your body will react to gluten like a toxin. It can damage your intestinal tract, causing diarrhea and other digestive symptoms.
In the mid-1990s, researchers realized that problems go further. Many people with celiac disease find that even small amounts of these problem grains cause fatigue and mental fuzziness. The good news is that by avoiding gluten, the symptoms vanish.
Testing for celiac disease is easy. Your doctor simply draws a blood sample to check for the antibodies that are the hallmark of the condition. If it looks like you have it, your doctor may perform a small bowel biopsy to check for damage. However, if you suspect you have a gluten problem, you can easily just go gluten-free for a few weeks without testing to see if your symptoms resolve. Let me hasten to add that if you are not sensitive to gluten (the vast majority of people are not), there is no health reason to avoid it.
If you would like to see what a gluten-free diet can do for you, simply avoid wheat, barley, and rye. You should have no problem with rice, corn, millet, quinoa, amaranth, or buckwheat; and vegetables, fruits, beans, tofu, and so on should be fine, too. But you’ll have to read labels, because if you have celiac disease, even the slightest trace of gluten, like the wheat in soy sauce or the barley in a canned soup, will cause a reaction.
Oats do not contain gluten, so in theory they should be okay. Unfortunately, some oat products harbor traces of other grains, which has led some companies (such as Bob’s Red Mill) to use special production facilities that prevent cross-contamination. You may find it prudent to strike oats off your grocery list at first, and then reintroduce them after your symptoms have settled down to see if they affect you one way or the other.
Many grocery stores carry gluten-free breads and other products. When you’re choosing restaurants, Indian, Mexican, and Middle Eastern fare will have the most choices, and local celiac or gluten-free support groups will have restaurant recommendations for your area.
If you have an untreated depression, your memory may feel like it has been switched off. It’s not just that you’re in an emotional funk. Your brain can’t seem to get in gear. But you will find that as depression lifts, either on its own or with medications, your memory will return to normal.
However, antidepressants are a mixed blessing, sometimes contributing to confusion and memory problems, as we saw above. I would suggest that you first explore nondrug treatments, particularly brief psychotherapy and exercise, and reserve medications for when these more natural methods do not do the job.
Not only does intoxication erase memories, but long-term drug or alcohol use destroys brain cells. If you are having more than one or two drinks a day, you’re getting into the danger zone.
That humble little organ at the base of your neck affects so many things, from metabolism to memory. The memory problems caused by thyroid disease are not usually very severe, but they can occur. Blood tests will easily show whether your thyroid is making too little or too much thyroid hormone.
Symptoms of low thyroid (hypothyroidism) are often vague—fatigue, weakness, and weight gain. But if the condition continues, you could develop an enlarged thyroid, along with a wide variety of problems: dull facial expression, drooping eyelids, hoarse speech, dry skin, brittle hair, menstrual problems, slow heartbeat, constipation, depression, and anemia. Treatment with thyroid hormone is effective and is often helpful in borderline-low cases, too.
Overly high levels of thyroid hormone can affect memory, too. Symptoms of hyperthyroidism include rapid heartbeat, palpitations, heat intolerance, weight loss, and menstrual irregularities. You could also have an enlarged thyroid and appearance of unusually prominent eyes, among other problems. Treatment usually consists of medications, radioactive iodine, or surgery, followed by thyroid hormone replacement.
Thyroid problems sometimes improve on their own, without treatment. You will want to consult with your physician to see whether treatment is necessary.
If the supply of oxygen to your brain is interrupted—even briefly—the results can be disastrous for the brain.
Perhaps the most dramatic situation is cardiac arrest. As the ambulance crew comes to your rescue and gets your heart beating again, your family breathes a sign of relief. But while your heart was stopped, your brain cells were on their own. There was no oxygen reaching them, and the result could be persistent memory deficits.
Similarly, heart bypass surgery is often followed by cognitive problems. While the finger of blame had first pointed to the heart-lung machine (cardiopulmonary bypass), memory problems occur even when the device is not used, suggesting that it may actually be due to some more fundamental problem in heart bypass surgery. The good news is that cognitive problems typically improve as the weeks go by.
Many kinds of infections can cause memory problems, so your doctor may think about several possibilities: Lyme disease, HIV, syphilis, and various kinds of encephalitis. The treatment is targeted to the specific organism.
Many people with migraines feel that their headaches do real mischief to their memory and ability to focus. And indeed, researchers have found that people with migraines have trouble with verbal memory, reaction time, and even just paying attention, both during and after headache attacks.5,6
The good news is that treating the migraine gets your brain working again. Sumatriptan nasal spray (20 milligrams) rapidly restores cognitive function.6
As I mentioned above, you will want to see if diet changes can knock out your migraines. They often do. Common migraine triggers include dairy products, chocolate, eggs, citrus fruits, meat, wheat, nuts, tomatoes, onions, corn, apples, and bananas. Some of these foods (such as citrus fruits) are perfectly healthy for most people. But just as people who are allergic to, say, strawberries need to steer clear of them, the same is true of any food that is triggering headaches. With a simple elimination diet (described in my earlier book Foods That Fight Pain), it is easy to check which of these foods might be your culprit, and then you’ll have power you did not have before.
Chemotherapy often causes cognitive problems, in addition to its many other side effects. Researchers at the University of Toronto found that about half of women undergoing chemotherapy for breast cancer had moderate to severe problems with memory and language skills.7 They also tested women who had finished their chemotherapy treatments more than a year earlier and found that about half had continuing cognitive problems that were at least moderate in severity.
Their memory problems were not psychological. That is, it was not that depression or anxiety was interfering with their concentration. The problem was physical. Their brain cells simply were not working as well as they had before.
The fact is, chemotherapy is terribly toxic, which is exactly why doctors use it. They are trying to poison cancer cells. Unfortunately, some common chemotherapy drugs may be even more toxic to brain cells than to the cancer cells they are targeting.8 As a result of these observations, many people are more and more cautious about chemotherapy.
Allow me to add diabetes to the list of memory threats. It is not that diabetes hurts your memory directly. Rather, people with diabetes are at heightened risk for Alzheimer’s disease and stroke.
In 1988, Japanese researchers invited more than one thousand adults to have their blood sugar levels tested with a glucose tolerance test. They then followed them over the next fifteen years. Those whose tests showed them to be prediabetic—with fasting blood sugars that were above the normal range but not high enough for a diabetes diagnosis—were 35 percent more likely than other people to develop any sort of dementia. Those whose blood sugars were in the diabetic range were 74 percent more likely to develop dementia.9
Our research team has developed the most powerful dietary program ever devised for diabetes. Many people have used it to bring their blood sugar under better control and to reduce or even eliminate their medications. The regimen includes three simple steps: following a low-fat vegan diet, avoiding added oils, and favoring low-glycemic-index foods, as we will see in more detail in chapter 9.
The conditions listed above are the most common problems affecting the brain. The list of potential problems also includes trauma, surgery, radiation, tumors, seizures, Parkinson’s disease, Huntington’s disease, and multiple sclerosis. In nonindustrialized countries, diets deficient in vitamin B1 (thiamine) or vitamin B3 (niacin) can also lead to serious memory problems, but these deficiencies are rare in developed countries, due to the widespread fortification of foods.
If you notice any change in your mental function, a check of the medicine cabinet and a good medical evaluation hopefully will identify the cause so that you can address it promptly.