Breaking Bad at the Pharmacy

April 25, 2014

By Medical Discovery News

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Drug abuse is not confined to street drugs like methamphetamine, heroin, and cocaine. America is facing an epidemic of prescription drug abuse, particularly with pain relievers, depressants, and stimulants. In 2010, 7 million Americans abused prescription drugs every month.

People are able to abuse such medications by taking medicines prescribed for someone else, using them in excess, or by taking them in a way not prescribed, such as crushing and snorting pills or liquefying and injecting them to hasten the effects needed to produce a high.

Depressants, sedatives, and tranquilizers are abused by more than 2.5 million people each month. The mood-altering drug Zoloft ranks sixth on the list of abused pharmaceuticals and earned more than $500 million in sales. It is prescribed for depression, obsessive compulsive disorder, post-traumatic stress disorder, and social anxiety disorder. The 10th most abused prescription drug is Xanax (alprazolam), called Xany, blue footballs, Xanybars, or just bars on the street. Xanax had sales of almost $275 million in 2012. This drug is intended to treat anxiety or panic disorders. It is often abused because it creates what is described as a sense of wellbeing, but can be fatal when abused.

The sleeping pills Ambien and Lunesta are the fourth and seventh most abused drugs from the pharmacy, with sales of $670 and $450 million respectively in 2012. Both are used to treat difficulties falling or staying asleep but can produce hallucinations when abused. Tom Brokaw of NBC News inadvertently experienced these symptoms from Ambien while covering the last presidential campaign.    

Drugs used to treat attention deficit hyperactivity disorder (ADHD) are also widely abused, usually by students seeking a way to stay awake and intensely focus on a project or test. Other than marijuana and synthetic marijuana, Adderall is the most-used drug by high school seniors and the eighth most abused prescription drug in the country. Its sales top $400 million. Other stimulants of the central nervous system, Ritalin and Concerta, are the third and fifth most abused pharmaceuticals. Stimulants can have significant side effects like irregular heartbeat, heart failure, seizures, and behavioral changes like paranoia or hostility. 

Some of the most abused drugs are opioid analgesics used clinically as pain relievers. These drugs are involved in 75 percent of all pharmaceutical overdose deaths – more than 16,000 people a year. An estimated 5.1 million people abuse these drugs each month. This included the most abused pharmaceutical drug – Oxycontin. In 2012, sales of this drug reached about $2.5 billion. The second most abused prescription drug, Suboxone, is used as a maintenance treatment for opioid dependence. Its sales brought in almost $1.4 billion. Another opioid, Opana ER (oxymorphone), ranks ninth on the list of most abused pharmaceuticals and is used to treat severe and chronic pain. It earned $300 million in sales in 2012.

Prescription drugs like these are a double-edged sword. They do a lot of good for a lot of people, and many genuinely need them to function. New regulations that govern the use of these drugs, while annoying for people who need them, help limit some of the abusive behavior of those breaking bad.

Sleeping Beauty For Real

May 3, 2013

By Medical Discovery News

“And when he saw her looking so lovely in her sleep, he could not turn away his eyes; and presently he stooped and kissed her, and she awaked, and opened her eyes, and looked very kindly on him.” So the Grimm Brothers ended their tale of “The Sleeping Beauty.” But for people suffering from primary hypersomnia, life is no fairy tale. Fortunately, they may have found a fairy godmother in the form of a neurologist named David Rye.

Hypersomnia causes symptoms like difficulty waking up from a long sleep, an increased need for sleep during the day even when working or engaged in a task, no relief from daytime naps, and a pattern of sleeping 14-18 hours per day. Hypersomnia is different from narcolepsy in that it does not come on suddenly and patients do not fall completely asleep, but function in a half-awake state. It is also quite rare.

Rye and his colleagues at Emory University in Atlanta have discovered a possible cause of hypersomnia. Certain drugs such as Valium or Xanax cause sleepiness by stimulating receptors for a chemical in the brain called gamma-amino butyric acid (GABA). As a result, when this chemical is absorbed through receptors, it inhibits activity in brain, slowing down functions in a way that leads to sleep. The scientists hypothesized that there might be a substance in the cerebral spinal fluid (CSF) of hypersomnia patients that also stimulates these receptors, leading to excessive sleepiness.

They collected CSF samples from 32 people with hypersomnia and a control group of those without. The fluid was added to cells that had been engineered with GABA receptors and could produce electrical activity. Scientists hoped to measure the absorption of GABA through the amount of electricity the engineered cells gave off when receptors were activated. At first, nothing happened. Then the scientists added a little GABA to the mix. Suddenly, the electric signals were twice as strong! The CSF from hypersomnia patients caused the receptors of engineered cells to be twice as sensitive to GABA. This suggests that hypersomnia patients have something in their CSF that enhances the effects of GABA, therefore dampening brain function. 

Rye doesn’t know what this special something in the CSF of hypersomnia patients is, but guesses that it may be a small protein made in the brain. So he created another study with a treatment in mind. Seven hypersomnia patients were injected with a drug called flumazenil, which is used to treat overdoses of Valium and related drugs. He thought that since hypersomnia patients’ brains act as if they are on such sedatives, why not try giving them an antidote? It worked – patients’ symptoms were reduced and they were more alert and vigil for up to a couple of hours. 

The next step is to conduct a bigger study to verify these exciting findings and identify the cause of hypersomnia. This is the first real hope for a treatment for hypersomnia; after all, a kiss from a prince is hard to come by.

For a link to this story, click here.

Grapefruit Juice – A Dangerous Mix

March 22, 2013

By Medical Discovery News

Millions of Americans sit down every morning with a cup of coffee, milk, or juice and take their daily medications. The problem? Depending on what’s in that cup, they may be putting themselves at risk for serious side effects or even death.

It’s not the coffee or the milk – it’s the juice, specifically grapefruit juice. A recent study in the “Canadian Medical Association Journal” identified 85 drugs that interact with grapefruit juice, of which 43 can cause serious problems. Many of these drugs are commonly prescribed for important medical conditions: Lipitor for lowering cholesterol, Nifediac for lowering blood pressure, Xanax for treating depression, oxycodone for pain relief, and even Viagra. 

When drugs are taken orally, they move through the stomach to the small intestine, where the majority of absorption to the bloodstream occurs. Once in the bloodstream, the drug begins to take effect and start working.

Then, the body starts to inactivate and break down drugs, first in the intestine and continuing in the liver, in order to be removed from the body. A superfamily of enzymes called cytochrome P450 is responsible for this. An important member of this enzyme family is CYP3A4, which processes about half the drugs in use today, including acetaminophen, codeine, diazepam, and erythromycin.

However, in addition to grapefruits, Seville oranges, tangelos, limes, and pomelos can also disrupt this process. They all contain furanocoumarins, which reduce the amount of CYP3A4 in the intestine. Without enough of this enzyme to start inactivating and breaking down the drug, more of it enters the bloodstream instead.

Too much of a drug in circulation can be toxic, causing damage to the liver and kidneys, gastrointestinal tract bleeding, respiratory failure, bone marrow suppression, and even death. For example, levels of the blood pressure medication filodipine in the blood are five times higher when it is taken with grapefruit juice instead of water.

Ironically, while it can be toxic when taken with some drugs, grapefruit can dampen the effect of others. For example, it reduces the absorption of the allergy medication Allegra, making it less effective. This may be because it blocks the specific proteins that transport Allegra cross the membranes of the gastrointestinal tract.

The influence of a single glass of grapefruit juice on a drug’s metabolism can last for up to 24 hours. And if someone drinks grapefruit juice more than once a day, the effect is amplified. However, since reactions differ among individuals, some people don’t react at all. Those on prescription medications should ask their doctor or pharmacist how to properly take them. To see a list of the 85 medications that interact with grapefruit, visit http://www.medicaldiscoverynews.com.

For a link to this story, click here.