Class Notes (839,460)
Canada (511,348)
PHAR 100 (175)
Lecture

25HerbalMedicine.pdf

5 Pages
113 Views

Department
Pharmacology and Toxicology
Course Code
PHAR 100
Professor
Hisham Elbatarny

This preview shows pages 1 and half of page 2. Sign up to view the full 5 pages of the document.
Description
Herbal Medicines Introduction • drugs derived from many sources ◦ 20 to 25% of prescription drugs derived from plants • herbal sales probably approaching two billion • ⅔ of world population depends on herbal medicines Relevance • over ¼ (perhaps1/2) of the Canadian adult population have taken a natural health product in the past year. • more than 1/2 of Canadians using complementary or alternative medicine do not disclose this to their physicians. • increasing number of natural health products for sale in Canada • most of these are sold through stores (including mail order) other than pharmacies • potential adverse interactions with conventional treatments • the potential for this increases when the doctor does not know that the patient is taking NHP Definitions • allopathic medicines: main stream drugs approved by Health Canada. (DIN) • herbal medicines: plant products sold as medicines – no approval • allopathic phytopharmaceuticals: compound or drug obtained from plants but full approval • homeopathy: the lower the concentration the greater the effect • food supplement: herbal product at ¼ the proposed therapeutic dose Why the move to herbals? • concern over the toxicity of allopathic medicines • high cost of allopathic medicines ◦ 50$ -200 000$ for prescription • lack of faith in allopathic medicines • hope for a cure for a chronic or terminal illness ◦ once cancer/other reoccurs for a third time ◦ amygdalin for cancer ▪ isolated from apricot seed, cyano compound ▪ said to be effective against some types of cancer (~20-30yrs ago) ▪ Cancer Society in US did clinical trials: no efficacy • belief that herbals are non-toxic ◦ not true • magic bullet: concept where always looking for key factor, one critical factor, that triggers cell to become a cancer cell • eventually have a target drug, the magic bullet, that will take out this factor • most lethal substance: anthrax force Value of plants for pharmaceuticals • direct source for therapeutic agent, e.g. Digoxin • source for raw materials for synthesis, eg. estrogens • structure of plant substance used as a model for new compounds ◦ cancer chemotherapy – Taxols. Problems Associated with Herbals • lack efficacy data ???? → not data show that they work, studies that have been done haven't been done with the same rigor as prescription drugs • lack safety data ???? • lack of quality control → being addressed: new regulation in 2004 • undeclared ingredients • intentional adulteration • source unknown and questionable • confusing literature -- what standards to be used ◦ want: same standards for prescription drugs • toxicities – some innocuous, others not • drug interactions with allopathic drugs Regulatory control • limited • should herbals be classed as drugs? • less regulatory control than OTC drugs Valerian - “herbalists' diazepam” • sedative and hypnotic ◦ contains valepotriates – shown to have CNS depressant activity with less adverse effect than diazepam • effect on sleep (From Trials) ◦ no difference in onset ◦ no difference in REM sleep -- which is good. ◦ no difference in quality of sleep vs placebo ◦ other studies small benefit – may be useful in mild insomnia – placebo? • safe but not effective – systematic review ◦ systematic review: look at all of studies being published ▪ make restrictions for which studies they are going to look out (ex: randomized, etc) Valerian continued Statistically significant vs Two studies. (2011) clinically significant • sleep quality in postmenopausal women ◦ placebo 4% reported improvement in sleep quality index ◦ valerian 530 mg 30 % reported improvement • Valerian in cancer patient. (RDBPC) ◦ 450 mg valerian vs placebo and measured PSQI (Philadelphia sleep quality index) over 8 weeks --- no difference in sleep Ex:when began to treat pneumonia w/ penicilin → in some ◦ controlled trial populations mortality rate ofpneumonia was hi
More Less
Unlock Document

Only pages 1 and half of page 2 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit