CESSATION OF SMOKING BY USING ZYBAN ORALLY
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DOXOFYLLINE: A NEW GENERATION XANTHINE BRONCHODILATOR
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VENOM FROM MARINE SNAILS FIGHTS AGAINST CANCER PAIN
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Bupropion hydrochloride (zyban )is an antidepressant phenyl–butamine of
aminoketone class chemically unrelated to tricyclic, tetracyclic or other
currently available antidepressants (e.g. selective serotonin-reuptake
inhibitors).
Mechanism
of action:
Bupropion is not a monoamine oxidase inhibitor, exerts effect on
5-hydroxytryptamine uptake, and minimally alters the reuptake of norepinephrine
at presynaptic sites. It is a weak inhibitor of dopamine reuptake,but its mechanism of action has not been clarified.
The precise mechanism of action responsible for the efficacy of Bupropion as an
adjunct in the cessation of smoking is unclear although reuptake inhibition of
noradrenaline and dopamine is involved, it has been suggested that central
nervous system (CNS) effects of dopamine might be involved in the reinforcement
properties of addictive drugs and that nicotine withdrawal manifestations
involve the absence of CNS effects of norepinefrine that is mediated by
nicotine.
Efficacy
of bupropion in smoking cessation does not
appear to depend on the presence of underlying depression.
Therapeutic
doses:
1-for
major depression:
The initial dosage ranges up to 200mg/d in divided amount. After a three
days of treatment, the dosage of bupropion in adults may be increased to 100mg
three times daily. After several weeks of treatment, in patients in whom no
clinical improvement is seen, the dosage may be increased gradually to 450mg/d
given in divided doses of more than
150mgeach, provided that there is clinical improvement at this level. If not,
bupropion is then discontinued.
2-For smoking cessation:
For use
in adults as an adjunct in smoking cessation,
the initial dosage of bupropion hydrochloride is 150mg daily for the first 3 days of therapy.
The dosage is subsequently increased in most patients to the usual recommended dosage of 150mg twice daily, which is
also the maximum recommended dosage. Dosages exceeding 300 mg daily should not
be used for smoking cessation because of the risk of seizures. Patients should
continue to receive bupropion hydrochloride for 7-12 weeks. Discontinuation of
therapy does not require tapering of the dosage.
Authors
have reported that about 30.3% of smokers treated with zyban stopped smoking
within a year, and that zyban has been twice more effective than nicotine
patches for helping smokers to stop smoking for one year at least.
REFERENCES:
Ellenhorn’s Medical Toxicology, 1997.
http://news.bbc.co.uk/hi/arabic/news/newsid809000/809287.stm
Doxofylline
[7 - (1,3 - dioxalan – 2 -ylmethyl) theophylline] is a novel xanthine
bronchodilator which differ from theophylline in that it contains a dioxalane
group in position 7. Similar to theophylline, its mechanism of action is related
to inhibition of phosphodiesterase activities, but in contrast it appears to
have decreased affinities towards adenosine A1 and A2
receptors, which may account for its better safety profile.
It is well known that cardiac rhythm disturbances are frequent findings
in patients with chronic bronchitis and emphysema. The pathogenesis of
arrhythmia is complex and many factors may
be involved, such as hypoxaemia, hypercapnia, respiratory acidosis, hypokalemia,
and concomitant ischemic heart disease.
Over the years, much attention has been drawn to possible arrythmogenic
effects of drugs such as theophylline, B- adrenergic agonists and digitalis, all
of which are commonly used in the treatment of chronic obstructive pulmonary
disease (COPD). These drugs may become hazardous because of direct stimulatory
effects, and therefore, should be used with caution.
The bronchodilating activities of doxofylline have been demonstrated in
clinical trials involving patients with either bronchial asthma or COPD. In
contrast to other bronchodilators, experimental and clinical studies have shown
that the drug is devoid of direct stimulatory effects. This may be of importance
because the arrythmogenic action of bronchodilators may have a negative impact
on the survival of patients with respiratory diseases.
In
patients with acute respiratory syndromes (acute asthma or exacerbation of
COPD), the administration of doxofylline (a bolus of 5 mg/kg followed by an
0.6mg/kg hourly infusion for 24 hours) was associated with a progressive
decrease in the heart rate that paralleledβthe clinical
improvement. The unique cardiovascular tolerability profile of doxofylline makes it unnecessary to
monitor the serum levels of the drug. This is also the reason why in clinical
studies it was not necessary to measure extensively the serum level of the drug
for the determination of the upper limit of its therapeutic range. To date, the
monitoring of the circulating concentration of doxofylline is recommended only
in cases of severely impaired
hepatic clearance or in the presence of concomitant therapies with quinolones.
REFERANCE:
http://www.medscape.com/librapharma/CMRO/2000/v16.no4/cmr1604.05.dini/cmr1604.05.dini-01.html
Kola is fruit of cola acuminata, an evergreen tree up to about 20 m high, native to Western Africa with long leathery leaves, and pods containing one to several fleshy and rosy seeds with more than two cotyledons each.
The part used is the dried seed from which the seed coat has been
removed. Dried kola contains caffeine, theobromine, tannins and phenolics
including d-catechin. L-epicatechin, kolatin. Also contains phlobabaphene,
anthocyanin, pigment kola red, betaine, protein and starch. All of these
substances are completely natural and most exist only when the nut is fresh.
The medicinal uses through out history include:
*increasing
the capacity for physical exertion and for enduring fatigue without food.
*stimulating
a week heart *impotence..
*treating
nervous debility. *weakness.
*lack
of emotion.
*depression.
*nervous
diarrhea.
*migraine.
*sea
sickness.
*anxiety.
Scientists are not completely sure how the nut does its magic, but it is
theorized that the mixture of agents in the nut work together to increase blood
flow, create euphoric state, and generally increase the desire to have sex.
Statements from women who have tried the nut have even indicated positive
results from them.
REFERANCES:
http://216.142.243.171/africanwood/
http://homeget,net/karcher//stories/kolanut.htm
http://www.natra-group.com/kolanut.hml
Ziconotide, a chemical component derived from the venom of predatory core
snails, which stab and paralyze passing fishes before eating them, has been
found to relieve severe pain in cancer patients.
Ziconotide is an analgesic rather than an anesthetic, so it relieves pain
without numbing the affected area.
The
authors tested ziconotide in a double-blind, placebo-controlled trial on 108
patients with cancer who had severe chronic pain. They administered ziconotide
through a catheter, which dripped the drug slowly into the patients’ spinal
fluid. Upon analysis of the drug trial data, the researchers found that
ziconotide was highly effective in relieving pain. Pain relief did not vary
depending on the age or sex of the patient. Ziconotide also worked equally well
regardless of whether the patient had previously been treated with morphine.
The
researchers have observed that ziconotide seems to be effective in treating pain
from nerve injuries as well as cancer pain. They also think that it might be a
good neuroprotective agent for people undergoing heart-lung bypass. This
promises to be the first of a whole new class of pain drug that may be able to
treat people resistant to other types of drugs.
REFERENCE:
http://pharmacistsmedscape.com/medscapewire/2001/05/medwire.0516.venom.html
أعلن
العلماء البريطانيين عن عقار جديد يساعد علي
الإقلاع عن التدخين وهو عقار الزيبان (بيبروبيون
هيدروكلوريد). ويعتبر
الزيبان من الأدوية المضادة للاكتئاب وليس له
علاقة بالأدوية المضادة للاكتئاب الثلاثية
الحلقة أو الرباعية الحلقة أو بالأدوية التي
تقوم بإيقاف تكسير السيروتونين وطريقة عمله
تعتبر غير واضحة حتى الآن. الإدمان علي
النيكوتين قد يكون في شدة الإدمان علي أقوي
المخدرات كالهيروين والكوكايين وخلال عشر
ثواني فقط من استنشاق الدخان من السيجارة حيث
تدخل جرعة من النيكوتين مباشرة وبسرعة إلي
المخ مما يؤدى إلى إفراز الدوبامين
والنورأدرينالين وعندما يقلع المدخن عن
التدخين فإن مستوي هذه المواد يتغير وهذا
بدوره يؤدى إلي الإحساس بالحاجة إلي
النيكوتين وزيادة القلق والتوتر. وما يفعله
الدواء الجديد هو تدخله في عملية الإدمان
ذاتها وذلك عن طريق إبقاء مستوي تلك المواد في
المخ علي ما كانت عليه قبل الإقلاع. وقد أظهرت
دراسة نشرت في أحد المجلات العلمية أن30,3% من
المدخنين الذين عولجوا بأقراص زيبان أصبحوا
غير مدخنين خلال عام.
يعتبر
دوكسيفيللين من العقاقير الجديدة الموسعة
للشعب الهوائية ويختلف عن عقار الثيوفيللين
في احتواء الأول علي مجموعة دايوكسيلين في
المركز رقم 7 وبالرغم من أن طريقة عمله لا
تختلف عن عقار الثيوفيللين في تثبيط إنزيم
الفوسفودايستيريز إلا أن درجة رغبته تجاه
مستقبلات الأدينوزين أ1 ، أ2 تكون أقل من عقار
الثيوفيللين وهذا يجعله أفضل من موسعات الشعب
الهوائية الأخرى في
أن تأثيره علي القلب أقل ولذلك فإن الأطباء
يستخدمون هذا العقار في مرضي القلب وبدون
الحاجة الدائمة لقياس مستوي العقار في الدم
ويلجأ الأطباء لهذا القياس عند استخدام
هذا العقار مع مرضي الكبد أو عند استخدامه في
نفس الوقت مع عقار من مجموعة الكينولين.
جوزة
الكولا (القورو) ثمرة
تنبت في وسط أفريقيا والأجزاء المستعملة فيها
هي البذور حيث تحتوى علي الكافيين
والثيوبروميين والتانين ومكونات أخرى
فينولية ولها استخدامات طبية عديدة منها علاج
حالات الضعف العام والضعف الجنسي والاكتئاب
والإسهال العصبي ودوار البحر وكمنشط للقلب.
تم
استخراج مادة كيميائية تسمى زيكوناتايد من سم
بعض القواقع المفترسة وقد وجد أن هذه المادة
تخفف الآلام الشديدة لمرضى السرطان بدون أي
تأثير مخدر وقد تبين من الدراسة التي تضمنت
عدد 108 من مرضى السرطان الذين أعطوا مادة
الزيكوناتايد ببطيء عن طريق قسطرة داخل
السائل الشوكي أن هذه المادة فعالة جداً في
تخفيف الألم ووجد أن تخفيف الألم لا يختلف من
مريض لآخر مهما اختلف العمر أو الجنس وكذلك
مهما تعاطي المريض مورفين من قبل أم لا.