Medicines That Affect Memory

Medicines That Affect Memory


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 article, we’ll look at the conditions that can harm your memory and what you can do about them.

Medicines That Muddle Memory

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.

crestorLipitor 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. 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.

lipitorDuane 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) 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. 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. 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.