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Archive for the ‘Drugs’ Category

New Cyanide Antidote

Posted by medliorator on December 28, 2007

University of Minnesota Center for Drug Design and Minneapolis VA Medical Center researchers have discovered a new fast-acting antidote to cyanide poisoning.

 

Current cyanide antidotes work slowly and are ineffective when administered after a certain point, said Steven Patterson, Ph.D., principal investigator and associate director of the University of the Minnesota Center for Drug Design.

 

Patterson is developing an antidote that was discovered by retired University of Minnesota Professor Herbert Nagasawa. This antidote works in less than three minutes – meeting the United States Department of Defense “three minute solution” standard. The research will be featured in the Dec. 27, 2007 issue of the Journal of Medicinal Chemistry.

 

The antidote was tested on animals and has been exceptionally effective, Patterson said. Researchers hope to begin human clinical trials during the next three years.

 

The antidote is also unique because it can be taken orally (current antidotes must be given intravenously) and may be administered up to an hour prior to cyanide exposure.

 

Because cyanide occurs naturally in pitted fruits, some grasses and other foods, and the body has mechanisms to detoxify small amounts in the diet. The new antidote takes advantage of this natural detoxification pathway by providing the substance the body naturally uses to convert cyanide to non-toxic thiocyanate.


U of M researchers discover fast-acting cyanide antidote
[EurekAlert]

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Med Student’s Drug Guide – Part 2

Posted by medliorator on December 23, 2007

SDN’s Alison Hayward, M.D. and Sarah M. Lawrence present a concise guide to narcotics:

Heroin
marketed by Bayer from 1898-1910 as a cough syrup and as a cure for morphine addiction, until the public discovered that heroin is merely an acetylated form of morphine which is not only converted to morphine as it is metabolized in the liver, but also is approximately twice as potent. Heroin is well-known as a highly addictive substance which can cause withdrawal symptoms after just a few days of use. Its classic effects include CNS/respiratory depression and miosis (pinpoint pupils). Withdrawal from heroin, referred to by patients as being “dope sick”, results in numerous unpleasant symptoms such as malaise, nausea and vomiting, diarrhea, muscle cramping and aches. You may note that your patients also begin yawning as they go into withdrawal. Withdrawal can be abruptly precipitated by the use of naloxone (Narcan), an opiate antagonist. This can have the unfortunate effect of causing the patient to go from a comatose state to an agitated, “dope sick” state which can be followed by the patient’s rapid departure against medical advice to seek more heroin. For this reason it is advisable to titrate naloxone by using small doses. It is important to note that however unhappy those in heroin withdrawal may be, withdrawal from heroin cannot kill you. Heroin is most commonly injected IV but can also be snorted or injected subcutaneously. Heroin plus cocaine injected IV is known as a ’speedball’.

 

Ketamine
a dissociative anesthetic… used in veterinary and human medicine. Classified as an NMDA receptor antagonist, ketamine induces a state known as dissociative anesthesia, in which signals from the conscious mind to other parts of the brain are blocked. Ketamine is primarily used in the induction and maintenance of general anesthesia, usually in combination with a sedative. Because it produces less respiratory depression than other anesthetics, Ketamine is useful in children and in emergency department patients with unknown medical histories. Besides its legitimate medical uses, Ketamine, or “Special K” is often used illicitly. Symptoms of Ketamine intoxication include sedation, hallucinations, a sense of bodily detachment, sensory distortions and unintelligible speech. No antidote exists and treatment is supportive.

 

PCP
phencyclidine is a dissociative hallucinogen that can be used either in crystalline or liquid form. In the liquid form, cigarettes or joints my be dipped in PCP then smoked. Its best known street name (though it has many) is “angel dust”. On a typical exam question, a patient will present to the emergency room with tachycardia, agitation, and potentially nystagmus or ataxia. The hallmark of phencyclidine on an exam question is that the patient will be engaging in highly violent behavior. The drug can cause behavioral disturbances as well as decreased pain sensation, the combination of these two factors increase the risk for violence.

 

GHB
GHB is known on the street as Grievous Bodily Harm, Georgia Home Boy or Liquid Ecstasy. It is a clear liquid that resembles water but has a slightly salty taste. Banned in the United States, GHB is nonetheless available for purchase on the internet or imported from other countries. Often sold in small bottles, GHB can be mixed with water or combined with other beverages to conceal its flavor. The ability to slip this substance into the drink of an unsuspecting victim, along with its sedative and amnestic properties have implicated GHB as a drug used in facilitated sexual assault.
The classic signs of GHB intoxication are CNS and respiratory depression, but GHB also has effects on other organ systems. Symptoms may include nystagmus, ataxia, seizures, vomiting, somnolence and aggression. Extreme CNS depression is most commonly observed in patients presenting to the ED with GHB overdose, but this CNS depression may resolve suddenly due to rebound effects from the drug. A patient may go from completely unresponsive to agitated and combative in a very short time frame.

 

Benzodiazepines
“benzos” are a class of prescription drugs with varying hypnotic, anxiolytic, sedative, anticonvulsant, amnestic and muscle relaxant properties. They are useful in the induction of anesthesia and the treatment of insomnia, anxiety, agitation, seizures, muscle spasms and alcohol withdrawal. Recreational users of stimulants may use benzos as a means of “coming down.”
Benzodiazepines exert their action at the GABA-A receptor in the CNS. Taken alone, benzodiazepines are considered very safe. When combined with other substances such as alcohol, serious or fatal CNS, respiratory or cardiovascular depression may occur. Symptoms of benzodiazepine intoxication include drowsiness, ataxia, confusion and vertigo.
Common benzodiazepines used in practice include alprazolam (Xanax), clonazepam (Klonopin), diazepam (Valium), lorazepam (Ativan), midazolam (Versed) and temazepam (Restoril). Rohypnol (flunitrazepam) is a type of benzodiazepine that is available in Mexico and Latin America and imported illegally into the United States. Particularly insidious are its amnestic properties and its tasteless, odorless formulation. These characteristics make “roofies,” as they are popularly known, a frighteningly effective tool in drug-facilitated sexual assault. The danger of this drug contributed to its inclusion in the Drug-Induced Rape Prevention and Punishment Act of 1996.

 

Drugs used for date rape such as Rohypnol and GHB can only be detected within a short time of ingestion on a drug screen, so if there is any question of their use, patients must be tested as soon as possible. Standard drug screens may not capture these chemicals; practitioners should make sure to specify the need to test for these drugs if their presence is suspected. This can be challenging as part of the drugs’ effectiveness is their ability to cloud the memory of their victims, leaving doubt about the events that transpired.

Raves, Rollin’, & Roofies: Your Guide to Club Drugs [Student Doctor Network]

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Med Student’s Drug Guide – Part 1

Posted by medliorator on December 23, 2007

SDN’s Alison Hayward, M.D. and Sarah M. Lawrence present a concise guide to narcotics:

Alcohol
Alcohol is a CNS depressant that appears to act mainly as an agonist on GABA receptors and a blocker at NMDA receptors. It is more correctly referred to as ethanol or “EtOH” because there are other types of alcohols, including methanol (solvent alcohol), acetone (nail polish remover), and ethylene glycol (antifreeze). All these are part of the classic “MUDPILES” acronym for anion gap acidosis, because they are metabolized to ketoacids.

  • One drink = 1 shot = 1 glass of wine = 1 beer, each drink should elevate the blood ethanol level by approximately 20mg/dL, and coincidentally, this is about the amount that is metabolized by the average person in one hour.
  • You must be able to identify alcohol withdrawal, for two reasons: one, it often presents in hospitalized patients who have not revealed that they are dependent on alcohol, and two, it can kill. Therefore, when a patient on the wards (or in a board question) becomes tachycardic, agitated/tremulous, diaphoretic, and hypertensive, if you are the only one on the team to think of ethanol withdrawal, you’ll look like a superstar. Classically (in a board question) the patient will have been in the hospital for about 3 days, but in reality, onset can be as early as a few hours after the last drink. Another presentation that should raise your antennae is a patient with no history of seizure disorder who has a seizure after a day or two in the hospital. These seizures do usually have a brief post-ictal state, and are often accompanied by the other manifestations of ethanol withdrawal. Ethanol levels are likely to be negligible or zero, but should be drawn.
  • The big names to associate with alcohol are Wernicke and Korsakoff – a.k.a Wernicke-Korsakoff syndrome, which is a result of thiamine deficiency related to alcoholism. Wernicke’s encephalopathy is ataxia, altered mental status, and ophthalmoplegia. It can progress to Korsakoff psychosis, in which patients cannot recall events and so they create improbable stories to explain what has happened. This is called ‘confabulation’. Many a medical student has been fooled by a confabulator. Remember – if a wild tale starts sounding way too wild to be true, you might be dealing with a confabulator.
  • ethanol is the treatment for methanol poisoning, because it competitively inhibits methanol turning into formate.

Cocaine
Cocaine can be used in a number of ways. While chewing on a coca leaf can make a user feel mildly euphoric for a few hours, smoking crack cocaine gives the user a rush before they even have time to exhale. Cocaine use results in tachycardia, but also can cause dangerous arrhythmias, and can precipitate myocardial infarction through coronary vasospasm. The mainstay of treatment is benzodiazepines.

 

Ecstasy
[MDMA] came to prominence in the 1960s and 1970s when it was used as part of psychotherapy, for which it appeared useful to facilitate communication as part of relationship counseling. It is a synthetic drug that is used in pill form. The most common concern for side effects of ecstasy is during its use at dance parties, when users may go for many hours without drinking enough water to stay hydrated. The combination of increased temperature and dancing can cause significant dehydration. Common effects include euphoria and increased appreciation of tactile stimuli. Ecstasy is unlikely to kill users and usually only results in death if combined with other drugs. Treatment is symptomatic.

 

Methamphetamine
known on the street as “speed” or “crank” – or just “meth.” [Methamphetamine is a powerful stimulant that] increases levels of brain dopamine significantly, resulting in increased movement and enhanced mood. Although methamphetamine is classified in DEA Schedule II, it is not widely prescribed
Methamphetamine can be taken orally, by snorting, by injection, or by smoking. Tolerance and addiction are often rapid. Symptoms of methamphetamine use include wakefulness, increased physical activity, loss of appetite, rapid heart and respiratory rates, increased blood pressure and hyperthermia. Users may experience insomnia, anxiety, confusion, tremor, convulsions, aggression, hallucinations, memory loss and severe dental problems. Treatment for methamphetamine addiction is challenging and should include cognitive-behavioral therapy to help break deeply entrenched patterns of abuse.

 

Mushrooms
When you hear people referring to “shrooms” as a hallucinogen, they’re generally referring to Psilocybin mushrooms, also known as “magic mushrooms”. Mushrooms that contain the compounds psilocybin or psilocin cause users to have hallucinations and feelings of euphoria that last about 6-8 hours. Contrary to popular belief, the effects are not due to the “poisonous” nature of the mushrooms. In fact, the National Institute of Occupational Safety and Health’s Registry of Toxic Effects rates psilocybin’s toxicity at 641 (with 1 being most toxic), compared to aspirin at 199 and nicotine at 21. A person would reportedly have to consume his or her own body weight in psilocybin mushrooms to take a lethal dose. Not surprisingly, then, treatment is mainly observation and supportive care until the effects wear off. Psilocybin can be much more dangerous when used with alcohol or marijuana, due to increased amounts of risky behavior. Unpleasant side effects can include nausea and vomiting.

Raves, Rollin’, & Roofies: Your Guide to Club Drugs [Student Doctor Network]

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Coffee Pros & Cons

Posted by medliorator on December 20, 2007

For moderate coffee drinkers (3-4 cups/day providing 300-400 mg/day of caffeine), there is little evidence of health risks and some evidence of health benefits.

The “Pros”

1. Antioxidants
2. Regular coffee consumption reduces the risk of Parkinson’s disease.
3. Coffee consumption is potentially protective against the development of type 2 diabetes.
4. Coffee drinking may protect against liver cirrhosis, especially alcoholic cirrhosis.
5. protective against gallstone formation
6. lowers the risk of kidney stones formation.
7. Improved mental performance.
8. Regular coffee consumption seems to protect against Alzheimer’s disease.
9. Caffeine can open airways and improve asthma symptoms.

The “Cons”

1. caffeine can increase the risk of heart attack, especially among those people who carry the “slow” gene variant for the enzyme that metabolizes caffeine. diterpenes cafestol and kahweol present in unfiltered coffee and caffeine each appear to increase risk of coronary heart disease. High quality studies have confirmed the cholesterol-raising effect of diterpenes. Coffee consumption is also associated with an increase of plasma homocysteine, a risk factor for coronary heart disease.
2. Heavy consumption of boiled coffee elevates blood total and LDL cholesterol. Unfiltered coffee contains two cholesterol-raising compounds cafestol and kahweol.
3. Coffee negatively affects the blood vessel tone and function (increases arterial stiffness and wave reflections).
4. Coffee can cause …cardiac arrhythmias
5. Although coffee consumption is not a significant risk factor for hypertension, it produces unfavorable effects on blood pressure and people prone to hypertension may be more susceptible.
6. Coffee intake may induce an extra urinary excretion of calcium. Heavy coffee consumption (4 cups=600 ml or more) can modestly increase the risk of osteoporosis, especially in women with a low calcium intake.
7. A cup of coffee can trigger heartburn.
8. High amounts of caffeine taken before going to sleep, can cause restlessness and difficulty falling asleep, tendency to be awakened more readily by sudden noises, and a decreased quality of sleep. However, some people can drink coffee and fall right asleep.
9. Dehydration.
10. Dependence. You may get a few days of headache and irritability if you choose to quit

The Pros and Cons of Coffee Drinking [Dumb Little Man]

Correlate: Drive Home Safely – Coffee vs Sleep

Correlate: Neuroprotective Effects of Caffeine

Posted in Drugs, Wellness & Health | 1 Comment »

Drive Home Safely – Coffee vs Sleep

Posted by medliorator on December 8, 2007

Driving home after exhaustive exams can be dangerous. French researchers compare caffeine and naps. Coffee wins.

Among 20- to 25-year-old drivers, the risk of line-crossing fell by 66 percent after a nap, and 74 percent after drinking caffeinated coffee.

Don’t forget the 3rd & safest option: postpone your journey until after a good night’s sleep.

For Sleepy Drivers, Coffee vs. Napping [New York Times]

Correlate: Neuroprotective Effects of Caffeine

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Chronic Pain Sufferer or Faker?

Posted by medliorator on June 5, 2007

From Chronic Pain or Drug Addiction by BENJAMIN BREWER, M.D. [The Doctor’s Office, WSJ.com]

Doctors are often accused of not adequately treating pain and being insensitive to patients’ needs. But they also have found themselves prosecuted or disciplined by licensing boards for prescribing too much pain medication. Trying to find a balance can be tricky.

 

Multiple calls to my house outside of office hours for pain meds is a red flag for a patient with a drug problem. So is using extraordinary measures to work around my on-call partner. I’ve seen both of these warning signs before.

 

Sometimes what patients really need is a drug-treatment program rather than a steady supplier for their Vicodin scripts. They doctor shop, and often come from a distance when every doctor in their own community and their local E.R. has wised up to their activities.

 

Patients with prescription-drug addiction seek narcotics by feigning or magnifying common ailments like chronic daily headaches, a bad back or chronic abdominal pain. They complain of pain from disorders that often can’t be objectively verified, and they often ask for their drug of choice by name. They claim to be allergic to essentially any pain medication that can’t give them a mind-altering buzz. Drug seekers tend to tell lies about their past evaluations and activities.

 

Having the old records is the key to the real story. A review of one patient’s records showed she had requested a refill of her medication after “her cat knocked it over in the sink.” She had told the same story to three different doctors over the span of five years.

 

Patients who call the office after a few days claiming intolerance to a drug I just prescribed are often looking to get an extra script of a similar drug. It worked the first time, but now I’m wise to the ploy.

via Kevin, M.D.

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