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Heroin:
Heroin is synthesized from morphine by a relatively simple
esterification reaction of two alcohol (phenol) groups with acetic
anhydride (equivalent to acetic acid). Heroin is much more potent
than morphine but without the respiratory depression effect.
A possible reason may be that heroin passes the blood-brain barrier
much more rapidly than morphine. Once in the brain, the heroin
is hydrolyzed to morphine which is responsible for its activity.
Synthetic narcotic analgesics may include the following:
Meperidine is the most common subsitute for morphine. It exerts
several pharmacological effects: analgesic, local anesthetic,
and mild antihistamine. This multiple activity may be explained
by its structural resemblance to morphine, atropine, and histamine.
Methadone:
Methadone is more active and more toxic than morphine. It
can be used for the relief of may types of pain. In addition
it is used as a narcotic substitute in addiction treatment because
it prevents morphine abstinence syndrome.
Methadone was synthesized by German chemists during Wold War
II when the United States and our allies cut off their opium
supply. And it is difficult to fight a war without analgesics
so the Germans went to work and synthesized a number of medications
in use today, including demerol and darvon which is structurally
simular to methadone. And before we go further lets clear up
another myth. Methadone, or dolophine was not named after Adolf
Hitler. The "dol" in dolophine comes from the latin
root "dolor." The female name Dolores is derived from
it and the term dol is used in pain research to measure pain
e.g., one dol is 1 unit of pain.
Even methadone, which looks strikingly different from other
opioid agonists, has steric forces which produce a configuration
that closely resembles that of other opiates. See the graphic
on the left and the top graphic on this page. In other words,
steric forces bend the molecule of methadone into the correct
configuration to fit into the opiate receptor.
When you take methadone it first must be metabolized in the
liver to a product that your body can use. Excess methadone is
also stored in the liver and blood stream and this is how methadone
works its 'time release trick' and last for 24 hours or more.
Once in the blood stream metabolized methadone is slowly passed
to the brain when it is needed to fill opiate receptors. Methadone
is the effective treatment for heroin addiction. It works
to smooth the ups and down of heroin craving and allows the person
to function nomrally. "Buprenorphine,
an analgesic originally used IV for pre/post surgical analgesia and
related, was approved not many years ago for opiate addiction treatment
(brand names Subutex and, with naxolone added to help reduce IV abuse, Suboxone.
It is provided as a sublingual tablet, available a many, but not all,
pharmacies. As a practical matter, a big advantage over methadone
is that it can be prescribed within a physician’s office setting, not a
“methadone clinic.” The prescribing physician has to be certified to
prescribe it, is issued a separate (2nd) DEA number, and is limited in
the number of patients that may be seen for this treatment.
Another advantage is that it does not have the abuse potential of
methadone; it merely fills the opiate receptors to eliminate physical
cravings. Onset of withdrawal from buprenorphine is slow, and the
symptoms of withdrawal are generally milder, when compared with
withdrawal from true opiates. It has been used in prison settings
to effectuate a fairly painless withdrawal process in as little as 5
days, although in a typical setting the patient will be weaned off
buprenorphine over a period of 4-8 weeks, and occasionally will
continue on a maintenance dose." See also: Buprenorphine
Credit: David Verizzo, Sarasota, FL
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