Codeine or 3-methylmorphine (a natural isomer of
methylated morphine, the other being the semi-synthetic 6-methylmorphine) is an opiate used for its analgesic, antitussive, antidiarrheal, antihypertensive, antianxiety, sedative and hypnotic properties, to suppress
premature labor contractions,myocardial infarction,
relief of skin irritation from itching, as well as many other uses.
Codeine is the second-most predominant alkaloid in opium, at up to three percent; it is much
more prevalent in the Iranian poppy (Papaver bracteatum),
and codeine is extracted from this species in some places although the
below-mentioned morphine methylation process is still much more common. It is
considered the prototype of the weak to midrangeopioids (tramadol,
dextropropoxyphene, dihydrocodeine, hydrocodone, oxycodone).
Codeine is marketed as both
a single-ingredient drug and in combination preparations with paracetamol (as co-codamol, e.g. brands Paracod,
Panadeine, Paramol, and the Tylenol with codeine series including Tylenol 3 and 4); with aspirin (as co-codaprin); or with ibuprofen (as Nurofen Plus). These combinations provide
greater pain relief than either agent alone (drug synergy). Codeine is also commonly marketed in products
containing codeine with other pain killers or muscle relaxers, as well as
codeine mixed with phenacetin (Emprazil With Codeine No. 1, 2, 3,
and 4), naproxen,indomethacin, diclofenac and others as well as more complex
mixtures including such mixtures as aspirin + paracetamol + codeine ± caffeine
± antihistamines and other agents such as those mentioned above.
Codeine-only products can be
obtained with a prescription as a time release tablet (e.g., Codeine Contin
100 mg and Perduretas 50 mg). Codeine is also marketed in cough
syrups with zero to a half-dozen other active ingredients, and a linctus (e.g.,
Paveral) for all of the uses for which codeine is indicated.
Injectable codeine is
available for subcutaneous or intramuscular injection; intravenous injection
can cause a serious reaction that can progress to anaphylaxis. Codeine suppositories are
also marketed in some countries
quote of codeine from wikipedia
BalasHapusCodeine were consumed are activated by the enzyme CYP2D6 in the liver to morphine, before experiencing the glusuronidasi, a detoxification mechanism for xenobiotics.
how codeine reaction formed in the liver resulting in morphine??
olin,i will try to answer your question,this is what i got from the article i have read.
BalasHapusmay it can help you...
Morphine is metabolized via two routes, namely hepatic and extra hepatik.Morfin glukoronat acid conjugated with hepatic whereas in extrahepatic pathways are more prevalent in the kidney. Approximately 75-85% of the morphine would be given morphine 3 glukoronat and 5-10% to 6 glukoronat morphine (ratio 9:1). Approximately 5% of the morphine would have demetilasi a small dansebagian normomorfin processed into codeine.
i'll try to give additional information about the converting of codein to morphin..
HapusThe liver converts codeine into morphine using the enzyme CYP2D6, a process that causes pain relief in most people. However, genetic differences in some people cause either too much or too little of the enzyme to be produced, resulting in less than pleasant results. People whose liver's produce higher than normal CYP2D6 levels convert more of the codeine into morphine — a situation that could cause excessive sedation, severe constipation and other side effects. People with less CYP2D6 find little or no relief from codeine, because the liver does not convert enough into morphine.
Certain medications can also affect one's CYP2D6 activity. The enzyme's production is inhibited, for example, by: diphenhydramine, a common antihistamine sold over-the-counter as Benadryl; and quinidine, a medication used to treat abnormal heart rhythm and sold under the brand names Duraquin, Quinaglute, Dura-tabs, and Quinidex.
how codeine act as an antitussive, analgesic and so on???
BalasHapusand please explain how the combination of codeine with paracetamol reaction that can produce a wide variety of drugs from a combination of both?
i'll try to answer yuli's question about how codeine act as an antitussive, analgesic and so on?
HapusDoctors sometimes prescribe pills containing combinations of codeine and over-the-counter (OTC) analgesics, such as Tylenol (acetaminophen) or aspirin, for pain relief after minor surgery, or for bone breaks and sprains, migraine headaches, or other pain that is expected to pass fairly quickly
According to Paul M. Gahlinger in Illegal Drugs: A Complete Guide to Their History, Chemistry, Use, and Abuse, codeine "is by far the most commonly used narcotic in the world," especially in the form of cough syrup. Codeine's qualities as a pain reliever have been recognized since the early 1800s. Chemically speaking, opiate medications such as codeine mimic the brain's own natural mechanisms for suppressing pain. Codeine actually reduces the ability of the brain's nerve cells to transmit pain signals. The reason it works better than the body's own mechanisms is because it floods the brain with chemical messages in a more powerful way than the brain's chemistry can on its own.