Search Results for "cannabis"

Aug 31 2010

Cannabis for chronic pain: Are we there yet?

Published by under Medicine,[Medicine&Pharma]

Marijuana is pretty popular stuff, and for good reason.  It is a potent drug, capable of both making someone feel good and of reinforcing dependence pathways in the brain.  Cannabis has been lauded for its ability to treat nearly any unpleasant symptom (except perhaps dry mouth), but so far evidence other than the anecdotal has been meager.

One of the areas where research has been a bit promising is in the treatment of certain types of nerve pain.  Small studies have shown some possible benefit in certain groups of patients, but robust studies are lacking.  In the U.S., this is certainly due at least in part to restrictions on cannabis research, but only in part.

Still, chronic nerve pain is an important problem, with imperfect treatments.  Opiates such as morphine are effective but come with significant side-effects.  Some anti-seizure medications such as gabapentin and pregabalin have shown some promise, but they are relatively expensive (although the price on gabapentin is dropping) and only somewhat effective.  Finding effective drugs, to be used either alone or in combinations, would help people suffering from a frustrating and sometimes disabling problem. Continue Reading »

14 responses so far

Nov 24 2009

Cannabis and cancer cachexia

Published by under Cancer,Medicine

One of the most frightening symptoms of advanced cancer is "cachexia", or severe, unintentional weight-loss and wasting. It's a terrible prognostic sign, and the only truly effective treatment is removal of the cancer. Treatment of this syndrome has the potential to improve quality of life in patients with advanced cancers. Various types of medications, including antidepressants, hormones, and cannabis derivatives have been tried with little effect. Treating the symptoms of incurable cancers is difficult and although we're pretty good at it, we sometimes fail. Cannabis seems a plausible intervention, given the anecdotal and clinical data associating it with increased appetite, although appetite in normal, healthy individuals may be mediated by different pathways than the cachexia in cancer patients. Still, it's worthy of investigation.

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Oct 27 2010

Uncommon suffering

Published by under Medicine

(I'm giving you fair warning: this is a long piece, but I've divided it up for you.  Each part will do fine on its own, but of course I'd like you to read both. You'll be a better person for it. --PalMD)

Part I: Uncommon Sense

Everything was OK until Christmas; before that she felt fine.  Then she began to feel tired.  She was having trouble sleeping so, she thought, maybe that was it.  She tried some sleeping pills from the drugstore, but she still didn't feel right.  Just doing a load of laundry wore her out.  She and her husband normally got together with the same set of friends every New Year's Eve, but this year she was too tired.   She hated New Year's Day, because every year she made another set of resolutions, usually about her weight.  When she got on the scale this year, she was up twenty pounds. Twenty pounds!  Impossible!  Her pants fit more or less the same, although her shoes were tight.  In fact, she'd been wearing unlaced shoes around the house and couldn't really fit into most of her socks.  She went to bed disappointed.

That night she woke out of a sound sleep and sat bolt upright---she couldn't breathe.  She ran to the window, threw it open, and gulped in cold air, slowly feeling better.  Her husband called an ambulance.

Heart failure is a condition in which the heart isn't pumping well enough to meet the body's needs.  Fluid can back up into the lungs, making it hard to breathe, the legs can become  swollen; and depending on the severity, heart failure can lead to sudden death.   One of the mainstays for the treatment of heart failure is a class of medications called diruetics which cause patients to urinate more, decreasing swelling and easing breathing.  But diuretics don't really affect the heart itself, they just drain off fluid, alleviating some symptoms.  It seems logical that if a failing pump is responsible for many of the symptoms of heart failure (and it is), then medications that improve the pumping action would be a good thing, and those that decrease it bad.  It's common sense.  It's intuitive.

Medical students and residents often dread discussions about statistics (a characteristic which I'm sure is not unique to these groups).  And who can blame them, really?  Statistical analysis is inherently non-intuitive.  Its purpose is to separate us from our own natural inclinations to identify patterns (our "intuition") in order to systematically study relationships between variables of interest.

A number of years ago, doctors noted that a certain class of drugs ("inotropes") improved the pumping action of the heart.  Patients with heart failure were given these drugs, and their heart function improved.  Common sense, right?  But when the topic was studied systematically, researchers found that these drugs actually increased mortality.  Oops (in this case, "oops" means people dying).

Another group of drugs called beta-blockers can reduce the pumping action of the heart, and for years were assiduously avoided in heart failure---until study after study showed that beta-blockers actually decrease mortality in chronic heart failure.

Common sense can give us a starting point, but until the big questions are examined systematically, we are in danger of intuiting our patients to death.  Beta blockers are now a mainstay of heart failure treatment, and inotropes a rarely-used footnote, a treatment reserved for a specific set of circumstances.  But we didn't figure that out through common sense alone.

Part II: Does smoking pot cause cancer? Continue Reading »

18 responses so far

Oct 14 2010

Should I lick this?

Published by under Medicine

When I lived in Northern California, I would often hear stories about people scouring the back country for psychedelic toads.  In popular imagination, these toad wranglers would then gather around bonfires and with great ceremony and earnestness, they would lick hapless bufoids until they (the humans) fell into ecstatic trances---and then vomited profusely. These stories, often parroted by local media, would end with the news that toad licking had finally been outlawed by the state.   The truth, as usual, is quite a bit more complicated.

Bufotenin, one of many molecules secreted by the skin and parotid glands of some toads of the genus Bufo, is classified by the DEA as a Schedule I drug.  This is the same class as heroin, mescaline, cannabis, and other drugs the DEA feels have a high potential for abuse and little or no therapeutic value.  Bufotenin is also present in certain mushrooms, so I wouldn't swear that is was outlawed because of a pandemic of toad licking.

But many toads are toxic.  While there are few reports in the literature about poisoning due to toad licking, there are plenty of reports of accidental toad poisoning.  Toads are a food product in parts of Southeast Asia.  There have been many reports of accidental toad poisoning in rural Laos, especially when toad skin and toad eggs are part of a meal.

But there's more than one way to get killed by a toad. A traditional Chinese herbal medicine called ch'an su *, which has been sold as an aphrodisiac, topical anesthetic, and a heart medicine, has been responsible for poisonings both in Asia and the U.S. (one of the versions sold in the U.S. was "marketed" as a topical medication, but was taken internally, perhaps for the hallucinogentic affects).  
Some of the chemicals present in toad venom are closely related to cardiac glycosides such as digoxin, a potent naturally-derived heart medication, and intoxication with toad venom closely resembles digoxin poisoning.  In fact, blood tests in victims are often positive for digoxin.  Given the similarities to digoxing poisoning, investigators have tried treating toad poisoning in a clever way. Digoxin (and toad) poisoning requires intensive medical care.  Even with close care, a patient can die of fatal heart arrhythmias.  But a couple of decades ago, an antidote was developed for digoxin poisoning.  Sheep are injected with digoxin and anti-digoxin antibodies are then isolated from their blood.  These antibodies are then chopped up so that only the "Fab" portion is present.  When given to a patient with digoxin toxicity, the Fab binds to circulating digoxin, preventing it from binding to other receptors in the body, and allowing it to be harmlessly excreted by the kidney.

Given how closely toad poisoning and digoxin poisoning resemble each other, and that toad toxins are similar enough to digoxin that they show up as digoxin in toxicology tests, it seems reasonable to think that the same antidote may work for both poisons.  This has been tested in several cases, with apparently good results (there data are limited by the small number of patients).

Cardiac glycoside poisoning is very dangerous.  It would appear that poisoning by sources other than regular medications has a high fatality rate.  Given this, it would seem reasonable to treat suspected toxicity with digoxin immune Fab.  The only catch is cost and availability.  If a kid in New York eats some Chinese toad venom, any hospital can administer the antidote.  If a woman in a small Laotian village eats a bad batch of toad soup, the cure may not be available.  The cost may also be prohibitive.  Each vial costs around $700, and it wouldn't be unusual to give 10 vials.

It may be hard to prevent toad poisoning among rural Laotians without solving societal problems of poverty and hunger.  But in this country we can easily avoid consuming potentially deadly herbal remedies.

*(a special shout-out to my buddy David Kroll who may be interested in this bit of history, if he doesn't already know it).

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3 responses so far

Sep 11 2010

Open letter to PZ Myers

Published by under Politics

Dear Paul,

I've read your writing for years, and have generally admired it.  While I haven't always agreed with you, we've generally seen eye-to-eye on the big issues.  It is out of my respect for you that I'd ask you to re-examine some of your thoughts about the recent non-burning of the Koran.

Of course it's legal to burn anything (well, usually not cannabis). But speech has consequences. These consequences are not always apparent to people, who may be blinded by their own beliefs, by their own position of privilege, etc. Your careless response to the aborted Koran burning fails on many levels, but especially on the level of empathy.

I've already argued that burning books is a form of expression that carries a lot of baggage.  You may feel like a despised minority due to your atheism, but I gotta tell you, from my perspective as an atheist and an ethnic minority, you're full of shit on this one.  Despite your atheism, you comes from a position of privilege that you are  perhaps too incredulous to see.   The first clue to this blindness comes early in your post:

People just aren't getting it; they're so blinded by an inappropriate attachment to magic relics that they're missing the real issues.

Yeah, but no.  The primary problem from the perspective of a white, male, employed atheist sitting in a house munching on lutefisk and aqvavit (don't you love stereotypes)  is that of people's inappropriate attachment to objects.  From the perspective of the poor, deluded people, it's the threat implied by the action of destroying something sacred to them.

Perhaps you didn't mean to erect such an enormous straw man to fight, but review this statement.  Humor me.

The problem isn't a few books being burned; that's not a crime, and it doesn't diminish anyone else's personal freedoms. The problem is a whole fleet of deranged wackaloons, including the president of the USA in addition to raving fundamentalist fanatics, who think open, public criticism and disagreement ought to be forbidden, somehow.

And seriously, this whole silly contretemps would have evaporated if a few people learned to shrug their shoulders and react rationally instead of feeding the fury with Serious Pronouncements and Reprovals.

Paul, the problem isn't the legality.  It does diminish people's personal freedoms.  It diminishes their sense of safety and security.  If I become afraid to practice my religion because of violent bigotry, I'm less free.  To tell me to get over it is some seriously fucked up victim-blaming.

I'm tempted to ask you the following question, but also afraid to.  If I could legally obtain a Torah for you, would you burn it? (I wouldn't but it's a thought experiment.)

If the answer is "no", then you're a hypocrite.  If the answer is "yes", then you have no understanding of history, of oppression, of fear.

Whether or not you think it appropriate, people imbue objects with meaning.  Why else try to save your house from burning down?  You have insurance, don't you?  But most people don't want to lose a house and the objects it contains because they have meaning.  Religious objects are no more or less irrationally revered than family photos.  People give them meaning.

It's appropriate to call out people on harmful beliefs, to criticize Catholic beliefs about homosexuality, Torah passages about rape, Koran suras about violence.  But collecting and burning religious texts is not simple criticism, it is an attack on the people who hold these texts dear, no matter how irrational they are.

To ignore this is to betray a sense of bigotry, one to which you may be blind.  Think of this as a gentle reminder.

In friendship and collegiality,

Peter

193 responses so far

Feb 22 2010

Clinical Marijuana Research Update

Published by under Medicine

Human beings are fundamentally narcissistic, and this narcissism can be antithetical to good science and good medicine. We place far too much confidence in our individual abilities to understand what happens to us, and we place far too much importance on our own experiences, inappropriately generalizing them. That's why science is so important in medicine---to avoid basing life-or-death decisions on something some guy thinks he might have heard once.
In my recent piece on medical marijuana in Forbes, commenters took me to task for what they perceived to be a host of errors in my reasoning. Some of these deserve to be specifically addressed, but not before a summary of the topic.
Marijuana's legal status is a political issue, not a scientific one. I will leave the politics to those cursed with such things. But I'm responsible for medical decisions, and as much as is possible, I have to look at data dispassionately. I have no doubt the individuals find marijuana beneficial for a wide range of problems---this may be a basis for study, but is not adequate data to prescribe a powerful pharmacologic agent.
In 2000, the University of California established the Center for Medicinal Cannabis Research. This month, they released a summary of results to date.

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24 responses so far

Nov 23 2009

Kid's got autism? Get 'em high!

Published by under Absurd medical claims,Medicine

Today over at Science-Based Medicine, Dr. Novella has a review of the so-called "biomed" movement in autism treatment. Anyone should be able to understand the desperation of parents with sick kids, but grief can lead to very bad decisions. As physicians, one of our jobs is to guide people away from these decisions and not to give false hope. Telling people what they want to hear might make you as a caregiver feel good, but as physicians, our goal is not to make ourselves feel good but to help others.

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62 responses so far

Nov 19 2009

Why I won't be prescribing medical marijuana

Published by under Medicine

In November, the citizens of my home state approved a medical marijuana law. The very next day, I started getting calls from patients (often not may own) asking how they could get it. I'm not fan of draconian laws that imprison people for getting stoned, but when it comes to medical interventions (rather than legal ones) I have an informed opinion. The new law allows Michigan residents to grow weed for their own consumption if they have approval. The law does not allow doctors to prescribe marijuana, rather it allows them to certify that the patient has a condition designated by statue as qualifying them for the medical marijuana program.
When I prescribe a pharmacologic intervention, I usually have some data to back up my decision. My most commonly prescribed medications, such as metformin, ACE inhibitors, beta blockers, statins, and aspirin, have clear dosing options and have clear outcome data that support their use. Marijuana is not a clearly science-based treatment.
That is not to say it isn't medically useful. There is a great deal of anecdotal data for its use in a variety of conditions, and there is scientific plausibility underlying this data. There are also data supporting the concept of cannabis dependence, and there is scientific plausibility to support the idea that smoking anything is probably bad for you. In other words, the available clinical data do not give a doctor a clear way to evaluate the risk/benefit ratio of pot.
In some circumstances, the decision is a bit more clear. In hospice patients or other patients with end-stage diseases, there is probably little harm in using cannabis, although we don't have a lot of data here either.
With marijuana, we have a drug that is not standardized, and has no clear indications for which it has been well-studied. There is no other drug whose use I would recommend on such scant data. There may be considerable promise in cannabis and its derivatives, but until the government allows more study, I'm not writing it.

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