Herbal medicines Flashcards
1
Q
What is a CAM
A
Complementary and alternative medicine.
The treatment of disease using methods other than recognised/conventional medicine.
Use of homeopathic, herbal, aromatherapy and over the counter vitamin supplements to treat conditions
Often not adequately clinically trialled
Might not have a product licence
2
Q
Why do people use herbal medicines
A
Used in developing countries where cost of drugs is prohibitive, poor accessibility to drugs in rural areas, shortage of physicians
Perception that natural = safe
“More” ADRs reported with conventional medicines than herbal preparations
Provide a sense of control, a mental comfort from taking action e.g. cancer, AIDS
Cultural & religious beliefs
Use differs by ethnic group, income, age & educational level
3
Q
Regulation of herbal meds
A
- Licensed: Marketing authorisation (product license) issued by Medicines and Health Care products Regulatory Agency (MHRA)
- Have to meet safety, quality and efficacy standards similar to conventional drugs
- Unlicensed: Exempt from licensing requirements (Section 12 of Medicines act 1968)
4
Q
Section 12
A
- Section 12 (1) person can make, sell and supply herbal remedy as part of business provided remedy is manufactured on the premesis and supplied as the consequence of a consultation between patient and herbalist
- 12(2) allows manufacture and supply where
- Process of manufacture consists of drying, crushing or comminuting
- Remedy sold without any written recommendation as to its use
- Remedy sold under a designation which only specifies the plant and the process and does not apply any other name to the remedy
5
Q
Effect on patients
A
Limited evidence with regard to adverse drug reactions
Little evidence with regards to drug interactions
6
Q
Problems
A
- Poor manufacturing process
- Adulteration to include toxic substances and conventional drugs
- Misidentification of herbs
- Substitution of herbs
- Varying strengths of preparations
- Incomplete labelling
- Incorrect dosage and instructions
- Potential for drug interactions
- Lack of knowledge re: interactions, ADRs
- Inappropriate use / misleading claims
7
Q
A
8
Q
WHy patients may not voluteer info
A
- Lack of awareness of the potential for adverse effects/interactions
- Don’t consider product to be a medicine
- Fear of censure
- Belief that the doctor/pharmacist doesn’t know about alternative medicines
9
Q
Reporting
A
- MRHA via yellow card scheme
10
Q
Reasonably effective herbals
A
- Aloe Vera (topical)
Arnica (topical)
Black Cohosh
Chamomile tea
Echinacea
Evening primrose oil
Feverfew
Garlic
Ginger
Ginkgo Biloba
Hawthorn
Peppermint tea
Saw Palmetto
Siberian Ginseng
St John’s wort
Valerian
11
Q
A
- For relief of joint pain
- An amino acid sugar made from shellfish (or laboratory prepared)
- Found naturally in the body
- Plays an important role in making glycosaminoglycans and glycoproteins - essential building blocks of many parts of joints, including ligaments, tendons, cartilage and synovial fluid
Cautions: - May alter glucose sensitivity
- Pregnant or breastfeeding
- Allergic to shell fish
- Increased risk of bleeding with Warfrin
12
Q
Echinacea
A
- ADRs - Relatively free of toxicity either topically or orally
- Mild allergic reactions reported
- Serious allergic reactions reported in patients with a Hx of asthma, atopy, allergic reactions
- Drug Interactions - Antagonises immunosuppressants
- Increased bleeding time
- Hepatotoxicity with certain drugs e.g. MTX
- Used to treat colds
13
Q
Ginkgo
A
- Used by elderly persons because of its ability to improve cognitive function in persons with Alzheimer’s and dementia.
- Reports of bleeding associated with ginkgo use have been reported.
- ADRs - generally infrequent & transient
- GI upset, headaches, dizziness
- Contact with whole ginkgo plant associated with severe allergic reactions
- Caution patients who are also taking Vitamin E, warfarin, aspirin, and low molecular weight heparin about the potential interactions with ginkgo.
14
Q
Flaxseed
A
- Flax is one of the oldest cultivated plants in the world.
- A bulk-producing, stool softening agent that lowers levels of cholesterol, triglycerides, and low-density lipoproteins.
- Binds to bile acids in the intestinal tract and interferes with the reabsorption of fats.
- When soaked, flaxseeds can bind with other drugs, especially cardiac glycosides rendering them unabsorbable.
- Take flaxseed wither two hours before or two hours after taking other meds.
- Concurrent use with laxatives and stool softeners should be avoided because of possible potentiation of the laxative effect
15
Q
Feverfew
A
- Most commonly used to reduce the number and severity of migraine headaches.
- Inhibits platelet activity, so it should not be taken concurrently with warfarin or other drugs that affect clotting.
- A member of the daisy family, it is contraindicated in patients with allergy to ragweed.
16
Q
Ginger
A
- Used and tested as an antinausea and antispasmodic agent with good results.
- Potent inhibitor of thromboxane synthetase.
- Prolongs bleeding times.
- If taking warfarin or other drugs that affect platelet activity, avoid ginger in tablet form.
17
Q
Kava Kava
A
- Relieves anxiety, nervousness, and tension.
- Does not affect alertness.
- Acts as a dopamine antagonist.
- May increase tremor and decrease response to anti-Parkinsonian meds.
- Potentiates alcohol
Potentiates tranquilizers
Potentiates antidepressants
Do not take any of these concurrently with Kava
17
Q
St Johns Wort
A
- Current research shows that it acts as a selective serotonin reuptake inhibitor (SSRI) Because of this, concurrent use with SSRIs is prohibited.
- Newest research suggests that it may act in the cytochrome P-450 of the liver.
Interferes with metabolism of certain protease inhibitors used in the treatment of HIV - Associated with photosensitivity.
Do not take concurrently with other photosensitizing herbs or drugs.
If taking St. John’s wort, limit sun exposure
18
Q
Ephedra alkaloids
A
Stimulant effects
Stimulate the brain
Increase heart rate
Constrict blood vessels
Expand bronchial tubes
Thermogenic effects
Increase in metabolism
Adverse effects include: – skin reactions, irritability, dizziness,
dehydration, headache, insomnia, irregular heartbeat, seizures,
heart attack, stroke and death
19
Q
Ginseng
A
- Used to support overall health and boost the immune system.
- May also be used to increase stamina, promote a sense of well-being, control blood pressure, and lower blood glucose levels.
- Excessive use may cause hypertension, and CNS stimulation.
- May also reduce opioid’s analgesic effects.
- May cause hypoglycemia in patients taking insulin or oral diabetic agents.
- Monitor blood glucose levels closely in patients who have been taking ginseng.
- May increase warfarin’s anticlotting effect
20
Q
Guarana
A
- Marketed as a CNS stimulant.
- Contains a high concentration of caffeine and is found in many antifatigue products.
- If taken in combination with Sympathetic Nervous System can cause cardiac arrest.
- May also decrease cerebral blood flow
21
Q
Grapefruit juice
A
- CYP3A4 also occurs in the cells of the small intestine’s absorbing surface
- Function to deactivate a proportion of all foreign chemicals (toxins) before they can be absorbed – includes drugs
- Grapefruit juice inactivates intestinal CYP3A4 (inhibits effect)
- Greater dose than normal of many drugs absorbed into bloodstream
- Can lead to excessive plasma drug concentrations - some are highly toxic in overdose
22
Q
Vit E
A
- vitamin E >1000u/day
coenzyme Q10 is structurally related to vitamin K - Others increase or decrease INR
- For patients on warfarin who want to use herbals, they need to have an INR checked within 1 week of starting on the herbal. For interacting substance which affect platelets like garlic, the INR is not changed but the risk for bleeding is increased.
- Meadowsweet and willow contain salicylates
23
Q
Patients most likely to have problems
A
- Multiple medications
HIV/AIDS
Cancer
Transplant
Treated with warfarin, digoxin, or other agents prone to drug interactions
Undergoing surgery
