The next category of drugs are hallucinogens. They include
the psychedelics, the dissociatives drug and the deliriants.
Now, psychedelics are classical hallucinogens.
So, when we talk about classical hallucinogens,
what we're talking about are psychodelic drugs.
These cause a change in thought, in mood, in perception, and
they often cause intellectual and memory impairment as well.
However, the amount of intellectual and memory impairment
is actually quite minimal compared to other drugs.
You often will have a stupor or a narcosis, but once again,
this is not a predominant effect of the hallucinogens,
particularly the psychodelics.
What you really see is altered perception.
Now they act through the 5-HT2 serotonin receptor.
LSD or mescaline or some of the most commonly known ones,
but we also have drugs like PCP, often called "angel dust".
We have serotonin releasing agents.
So, they are the substituted MD drugs.
So, it can be MDMA or ecstasy or MDA. There's a whole class
of them that we can cover, and I did cover in previous lectures.
And then of course, there are the cannabinoids.
The most common of course is marijuanna,
but then we also have the new synthetic cannabinoids
that have recently entered onto the market.
The dissociative drugs act predominantly through the NMDA
receptor. They produce an analgesia, amnesia and derealization.
They cause dissociative perception. And they cause
clinically horizontal and vertical nystagmus
and marked hypertension and seizures. So, when you
have a patient show up and they are delirious
and you can't really communicate with them on
one on one basis, and they are imagining things.
Look at their eyes, and if they're having horizontal and
vertical nystagmus, they are not on a classic hallucinogen
or psychodelic drug, they are on one of the dissociatives.
Ketamine, or "special K" on the street, is probably the
most commonly used and most well known dissociative drug.
We use it in anesthesia all the time. Other drugs include
dextromethorphan which is often put in cough syrup
and cough tablets.
Nitrous oxide is often used in dental anesthesia.
And PCP or "angel dust" also act at the serotonin receptor,
and this cause dissociative symptoms as well.
The next category of drugs are deliriants.
So, these induce a delirium with extreme confusion
and they are absolutely unable to control their actions.
They are anticholinergic agents,
so they cause a lot of toxic effects
with respect to the anticholinergic axis.
Dehydration, mydriasis or dilated pupils are
very very common. So, look at the pupils, once again,
if they have a lot of nystagmus,
they're on one of the dissociative drugs,
if they have very dilated pupils, that's an anticholinergic
effect, and you should be thinking about drugs like ketamine.
Now, the interesting thing about these drugs
is they actually don't necessarily cause sedation.
And in fact, they were first used by warriors in Sparta
before they went into battle so that they would have no fear.
And here's some of the plant based origins.
Belladonna comes from a plant called nightshade,
and I've got it illustrated up in the top here.
And Jimson weed is another example,
and these are things that are sometimes picked by patients or
abusers, and they ingest the drug directly from the plant source.
Angel's trumpet is a plant that can cause a lot of delirium.
Mandrake, made famous by the Harry Potter movies,
is also another drug that is derived from a plant.
Uncured tobacco can act as a deliriant.
And benadryl and dramamine, which are common antinauseant
medications, are sometimes used as deliriants as well.
Let's talk specially about PCPs. So, I talked to you about "angel
dust" before, and I mentioned it briefly in the other lectures,
it is classified as the most dangerous drug by the FDA.
It causes psychotic reactions.
And often people who've committed murder were on PCP
or under the influence of PCP.
I had mentioned to you before that it causes vertical and
horizontal nystagmus, high temperatures, tachycardia,
hypertension, dry skin and seizures.
The problem with PCP in diagnosing a PCP overdose
is that your blood chemistry is essentially normal.
So this is a very hard clinical situation to figure out
because people come in, they are absolutely off the wall,
and they have a normal blood chemistry.
I also want to talk about something called "soap".
It is MDPV but we will know what is "soap" on the street.
And this is something that really showed up a few years ago
in Florida, and has just taken the country by storm.
It is either smoked or injected or snorted or ingested.
It causes a non-rewarding dose of alcohol
to become very rewarding. So, a small drink,
maybe one shot, all of a sudden gives them the effect
of drinking eight or nine shots or nine ounces of alcohol.
It cannot be detected by dogs, and cannot be detected in
standard urinalysis. You have to have special urinalysis.
So, it's a horrible drug. It's just starting to take off.
I don't know what will happen over the next 5 or 10 years,
but hopefully this drug
never becomes as mainstream as the others.
One of the mainstream drugs that's out there today
are cannabinoids or marijuanna.
The active agent is THC, but we also have cannabidiol and
other agents that are active that do cause the effect.
Now, some of the derivations of cannabinoids is "hash".
So, hashish or hash, is a purified paste that's
made from marijuanna. And hash oil is
a purification of the hash paste.
Initially, it causes presynaptic release of
dopamine and serotonin.
So, it generally gives a feeling of wellbeing,
and you know, not to care in the world.
After a while, it causes tachycardia.
A low dose can cause depression in young adults.
One of the problems with cannabinoids use in young people
is that it's little as a half joint, once a week,
leads to three times increase in depression
in people under the age of 25.
So, although people tend to think of it as a nontoxic agent,
or a nontoxic drug, it actually is quite toxic,
and it does have long term effects,
particularly on young people.
Now, some of the drugs that we've derived from the cannabinoid
receptor based plants, are now being used in cancer patients.
So, you can actually purchase pills
like these two that I've mentioned here,
one to treat obesity,
and one to treat nausea in cancer patients.
The nice thing about these drugs
and the nice thing about the medical marijuanna
strategy is that it can cause a reduction in nausea
in patients who are receiving cancer therapy
without causing them to become anorexic. So, they actually
maintain their diet and they maintain their hunger.
And in terms of treating obesity,
it seems counterintuitive that these people would benefit,
but it actually has some clinical benefit.
Now, they do not get high from these particular drugs because
they're not given in concentration high enough
to cause that effect.