Raw Garlic Consumption and Risk of Liver Cancer: A Population-Based Case-Control Study in Eastern China

Although the major risk factors for liver cancer have been established, preventive factors for liver cancer have not been fully explored. We evaluated the association between raw garlic consumption and liver cancer in a large population-based case-control study in Eastern China. The study was conducted in Jiangsu, China, from 2003 to 2010. A total of 2011 incident liver cancer cases and 7933 randomly selected population-controls were interviewed. Epidemiological data including raw garlic intake and other exposures were collected, and serum markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were assayed. Overall, eating raw garlic twice or more per week was inversely associated with liver cancer, with an adjusted odds ratio (aOR) of 0.77 (95% confidence interval (CI): 0.62–0.96) compared to those ingesting no raw garlic or less than twice per week. In stratified analyses, high intake of raw garlic was inversely associated with liver cancer among Hepatitis B surface antigen (HBsAg) negative individuals, frequent alcohol drinkers, those having history of eating mold-contaminated food or drinking raw water, and those without family history of liver cancer. Marginal interactions on an additive scale were observed between low raw garlic intake and HBsAg positivity (attributable proportion due to interaction (AP) = 0.31, 95% CI: -0.01–0.62) and heavy alcohol drinking (AP = 0.28, 95% CI: 0.00–0.57). Raw garlic consumption is inversely associated with liver cancer. Such an association shed some light on the potential etiologic role of garlic intake on liver cancer, which in turn might provide a possible dietary intervention to reduce liver cancer in Chinese population.

Garlic intake and gastric cancer risk: Results from two large prospective US cohort studies

Although many case-control studies suggested that garlic intake may reduce gastric cancer risk, evidence from prospective cohort studies has been lacking. We examined the association between garlic intake and subsequent risk of gastric cancer among 77,086 women in the Nurses' Health Study (1984-2014) and 46,398 men in the Health Professionals Follow-Up Study (1986-2014). Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models. We additionally examined garlic intake in relation to Helicobacter pylori (H. pylori) infection among 613 participants using logistic regression. During up to 30 years of follow-up, 292 participants were diagnosed with gastric cancer. The pooled multivariable RR of gastric cancer among participants who ate garlic, as compared to those who did not, were 1.11 (95% CI = 0.81-1.51) for the intake of garlic less than once per week, 0.98 (95% CI = 0.71-1.36) for one to four times per week and 1.39 (95% CI = 0.89-2.17) for five or more times per week (p for trend = 0.23). Similarly, no statistically significant association was observed cross-sectionally between garlic intake and H. pylori infection (comparing five or more times per week to never, pooled multivariable odds ratio = 1.66, 95% CI = 0.89-3.09; p for trend = 0.11). The findings from this large prospective study do not support the hypothesis that high garlic intake reduces risk of gastric cancer.

Garlic Burn to the Face

Topical burns from the use of garlic have been reported rarely in the medical literature. Most cases have resulted from the use of naturopathic or home remedy treatments. A 20-year-old male military Servicemember presented to a military wound care clinic 7 days after applying a homemade topical preparation of garlic to the zygomatic region of the right side of his face. The patient had consulted the Internet for treatment of a minor skin lesion in that area. He created a garlic paste, applied it to the affected area, and covered it with a dressing. Twelve hours later, he noted an intense burning sensation where he had applied the garlic paste. After the initial blistering, the patient recovered without any additional treatment. Second-degree burns were an unintended consequence of the use of garlic as a home remedy.

Garlic for the common cold

Background Garlic is alleged to have antimicrobial and antiviral properties that relieve the common cold, among other beneficial effects. There is widespread usage of garlic supplements. The common cold is associated with significant morbidity and economic consequences. On average, children have six to eight colds per year and adults have two to four.Objectives To determine whether garlic (Allium sativum) is effective for the prevention or treatment of the common cold, when compared to placebo, no treatment or other treatments.Search methods We searched CENTRAL (2014, Issue 7),OLDMEDLINE (1950 to 1965),MEDLINE (January 1966 to July week 5, 2014), EMBASE(1974 to August 2014) and AMED (1985 to August 2014).Selection criteria Randomised controlled trials of common cold prevention and treatment comparing garlic with placebo, no treatment or standard treatment.Data collection and analysis Two review authors independently reviewed and selected trials from searches, assessed and rated study quality and extracted relevant data.Main results In this updated review, we identified eight trials as potentially relevant from our searches. Again, only one trial met the inclusion criteria.This trial randomly assigned 146 participants to either a garlic supplement (with 180 mg of allicin content) or a placebo (once daily)for 12 weeks. The trial reported 24 occurrences of the common cold in the garlic intervention group compared with 65 in the placebo group (P value < 0.001), resulting in fewer days of illness in the garlic group compared with the placebo group (111 versus 366). The number of days to recovery from an occurrence of the common cold was similar in both groups (4.63 versus 5.63). Only one trial met the inclusion criteria, therefore limited conclusions can be drawn. The trial relied on self reported episodes of the common cold but was of reasonable quality in terms of randomisation and allocation concealment. Adverse effects included rash and odour. Authors' conclusions There is insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold. A single trial suggested that garlic may prevent occurrences of the common cold but more studies are needed to validate this finding. Claims of effectiveness appear to rely largely on poor-quality evidence.

Chemical burn caused by topical application of garlic under occlusion

Allium sativum (garlic) can cause an irritant contact dermatitis, secondary to naturopathic practices. We report an unusually severe case of chemical burn following garlic applied under occlusion.

Anaphylaxis induced by ingestion of raw garlic

Patients allergic to garlic often present dermatitis, rhinitis, asthma, and urticaria after ingestion of garlic, contact with garlic, or exposure to garlic dust. Garlic-related anaphylaxis is rare, and the impact of heating on garlic allergens is not very clear. We report a case of anaphylaxis induced by ingestion of raw rather than cooked garlic with manifestations different from previous reports, and we hypothesized that heating could reduce the allergenicity of garlic. Serum total immunoglobulin E (IgE) and specific IgE were tested using the Phadia CAP System FEIA (Phadia, Uppsala, Sweden). Protein extracts from raw and cooked garlic were analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Serum-specific IgE for garlic was 8.16 kUA/L. IgE banding proteins could only be detected in raw garlic extract, because allergens in garlic were mostly degraded into small fragments after heating, as shown in SDS-PAGE profile. In conclusion, raw garlic could induce life-threatening anaphylaxis. However, most of its allergens are heat labile, and patients allergic to garlic might tolerate the cooked one well.

Garlic for the common cold

BACKGROUND

Garlic is alleged to have antimicrobial and antiviral properties that relieve the common cold, among other beneficial effects. There is widespread usage of garlic supplements. The common cold is associated with significant morbidity and economic consequences. On average, children have six to eight colds per year and adults have two to four.

OBJECTIVES

To determine whether garlic (allium sativum) is effective for either the prevention or treatment of the common cold, when compared to placebo, no treatment or other treatments.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2011, Issue 4), which includes the Cochrane Acute Respiratory Infections Group Specialised Register, OLDMEDLINE (1950 to 1965), MEDLINE (January 1966 to November week 3, 2011), EMBASE (1974 to December 2011) and AMED (1985 to December 2011).

SELECTION CRITERIA

Randomised controlled trials of common cold prevention and treatment comparing garlic with placebo, no treatment or standard treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed and selected trials from searches, assessed and rated study quality and extracted relevant data.

MAIN RESULTS

Of the six trials identified as potentially relevant from our searches, only one trial met the inclusion criteria. This trial randomly assigned 146 participants to either a garlic supplement (with 180 mg of allicin content) or a placebo (once daily) for 12 weeks. The trial reported 24 occurrences of the common cold in the garlic intervention group compared with 65 in the placebo group (P < 0.001), resulting in fewer days of illness in the garlic group compared with the placebo group (111 versus 366). The number of days to recovery from an occurrence of the common cold was similar in both groups (4.63 versus 5.63). Only one trial met the inclusion criteria, therefore limited conclusions can be drawn. The trial relied on self reported episodes of the common cold but was of reasonable quality in terms of randomisation and allocation concealment. Adverse effects included rash and odour.

AUTHORS' CONCLUSIONS

There is insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold. A single trial suggested that garlic may prevent occurrences of the common cold but more studies are needed to validate this finding. Claims of effectiveness appear to rely largely on poor-quality evidence.

Complementary and alternative medicine in epistaxis: a point worth considering during the patient's history

A large number of patients take complementary and alternative medicine (CAM) for a variety of reasons, but most do not inform their physicians. This has implications for safety, as many forms of herbal CAM are thought to have a variety of side-effects and may interact with conventional medicines with potentially adverse consequences. We present the case of an otherwise healthy 25-year-old man with difficult-to-control epistaxis. On further questioning, we learnt that he had recently started self-medicating with a combination of aspirin, garlic tablets and milk thistle. Garlic increases bleeding time and milk thistle alters the function of liver enzymes, both of which may have contributed to the difficulty in his management of epistaxis. This case highlights the importance of asking about CAM use when taking a patient's history, as it may have implications for management.

Garlic: empiricism or science?

Garlic (Allium sativum L. fam. Alliaceae) is one of the best-researched, best-selling herbal remedies and is also commonly used as a food and a spice. Garlic constituents include enzymes (for example, alliinase) and sulfur-containing compounds, including alliin, and compounds produced enzymatically from alliin (for example, allicin). Traditionally, it has been employed to treat infections, wounds, diarrhea, rheumatism, heart disease, diabetes, and many other disorders. Experimentally, it has been shown to exert antilipidemic, antihypertensive, antineoplastic, antibacterial, immunostimulant and hypoglycemic actions. Clinically, garlic has been evaluated for a number of conditions, including hypertension, hypercholesterolemia, intermittent claudication, diabetes, rheumatoid arthritis, common cold, as an insect repellent, and for the prevention of arteriosclerosis and cancer. Systematic reviews are available for the possible antilipidemic, antihypertensive, antithrombotic and chemopreventive effects. However, the clinical evidence is far from compelling. Garlic appears to be generally safe although allergic reactions may occur.

Garlic for the common cold

BACKGROUND

Garlic is alleged to have antimicrobial and antiviral properties that relieve the common cold, among other beneficial effects. There is widespread usage of garlic supplements. The common cold is associated with significant morbidity and economic consequences. On average, children have six to eight colds per year, and adults have two to four.

OBJECTIVES

To determine whether garlic (allium sativum) is effective for either the prevention or treatment of the common cold, when compared to placebo, no treatment or other treatments.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 1), which includes the Acute Respiratory Infections Group Specialised Register; OLDMEDLINE (1950 to 1965); MEDLINE (January 1966 to March Week 3, 2009); EMBASE (1974 to March 2009); and AMED (1985 to March 2009).

SELECTION CRITERIA

Randomised controlled trials of common cold prevention and treatment comparing garlic with placebo, no treatment or standard treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed and selected trials from searches, assessed and rated study quality, and extracted relevant data.

MAIN RESULTS

Of the five trials identified as potentially relevant from our searches, only one trial met the inclusion criteria. This trial randomly assigned 146 volunteer participants to either a garlic supplement (with 180 mg of allicin content) or a placebo (once daily) for 12 weeks. The trial reported 65 occurrences of the common cold in the placebo group compared with 24 in the garlic intervention group (P < 0.001). The number of days of illness was lower in the garlic group compared with the placebo group (111 versus 366). The number of days to recovery was similar in both groups (4.63 versus 5.63). Because only one trial met the inclusion criteria, limited conclusions can be drawn. The trial relied on self-reported episodes of the common cold, but was of reasonable quality in terms of randomisation and allocation concealment. Adverse effects included rash and odour.

AUTHORS' CONCLUSIONS

There is insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold. A single trial suggested that garlic may prevent occurrences of the common cold, but more studies are needed to validate this finding. Claims of effectiveness appear to rely largely on poor quality evidence.

Four common herbs seen in dental practice: properties and potential adverse effects

The use of herbal supplements in North America is steadily growing and raises concerns about safety, efficacy, and how they affect safe patient care. The most notable and direct health risks associated with herbal supplements include hypertension, prolonged bleeding, and the potential for drug-herb interactions, which is of particular concern for patients undergoing anesthesia, both general and local anesthesia. In this article, four of the most commonly used herbs today in North America will be discussed: garlic, gingko, ginseng, and ginger. The pharmacology, benefits, and possible side effects of these herbs will be presented. Awareness of the rising use of herbs is important to prevent, recognize, and treat potential problems that can arise from herbal preparations taken alone or in conjunction with prescription medications.

The effect of silver nitrate, chloroformic garlic extract, and normal saline in induction of sclerosing cholangitis in rabbits

OBJECTIVE

To evaluate the effects of 0.5% silver nitrate, 20% chloroformic garlic extract, and 0.9% normal saline in induction of sclerosing cholangitis in the bile ducts of rabbits.

METHODS

During a-6-months period from April to September 2006 in Shiraz University Laboratory Animal Research Center, we selected 3 equal groups of rabbits. We injected 0.5% silver nitrate, 20% chloroformic garlic extract, and 0.9% normal saline into the bile ducts of each group. The animals were euthanized, and autopsied after 4 months and the liver and bile ducts were removed and studied histopathologically. Cholangiography was undertaken to evaluate the presence and extent of any sclerosing cholangitis.

RESULTS

Animals showed sclerosing cholangitis in silver nitrate group (7 [58%]), one (8%) in chloroformic garlic extract group and one (7%) in normal saline group. The difference between silver nitrate and chloroformic garlic extract groups were statistically significant and similar results were noticed between chloroformic garlic extract and normal saline groups.

CONCLUSION

Twenty percent of chloroformic garlic extract had fewer complications such as sclerosing cholangitis, compared to other materials.

Garlic burn as self-inflicted mucosal injury--a case report and review of the literature

Garlic is considered a valuable herbal medicine and has been used for centuries for treatment of various ailments. Along with its benefits comes some adverse effects. The present case describes chemical burn of oral mucosa caused by crushed garlic. To relieve toothache, the patient placed crushed garlic cloves in the buccal vestibule overnight and developed garlic burn injury manifesting as slough and ulceration in that region. Diagnosis was made on the basis of definitive history elicited from the patient. Topical anesthetic and antibacterial agents were advised for local application, and systemic analgesic was prescribed. The patient was referred to the Department of Endodontics for further treatment of the toothache. Garlic burn should be considered in the differential diagnosis for chemical burn if the burn is not found to be associated with other common factors, and history taking should include questions regarding use of herbal products, home remedies, and alternative medicine. Possible adverse effects of these methods should be considered.

Studies on the deodorization by mushroom (Agaricus bisporus) extract of garlic extract-induced oral malodor

The deodorizing effect of the mushroom (Agaricus bisporus) extract on the malodor produced after garlic consumption was investigated using an electronic sensor and sensory evaluation measurements. Comparative gas chromatography analysis revealed that the quantity of methane- and allylthiols that were usually found after garlic solution rinse, significantly fell after mushroom extract rinsing. Furthermore, in-vitro analysis (mixing the garlic solution and mushroom extract) showed that the methanethiol reaction with the mushroom extract proceeded faster than that of the allylthiol. Ab initio calculations implicated an addition reaction as the possible mechanism between the thiol compounds and the polyphenols. In comparison to the methanethiol, the higher activation energy required by allylthiol for a feasible reaction path way with the model acceptor, o-quinone, is expected to contribute to the difference in the rate of the reaction.

Contact dermatitis due to Allivum sativum and Ranunculus illyricus: two cases

Plants are of relevance to dermatology for both their adverse and beneficial effects on skin and skin disorders respectively. Virtually all cultures worldwide have relied historically, or continue to rely on medicinal plants for medical care. As alternative herbal remedies are becoming more widely used there is an increase in phytocontact dermatitis. Here we document two patients who developed contact dermatitis due to Allivum sativum, and Ranunculus illyricus after applying to the skin in order to relieve the rheumatological joint pain.

An examination of the bleeding complications associated with herbal supplements, antiplatelet and anticoagulant medications

Dental professionals routinely treat patients taking prescription, nonprescription, and herbal medications that are known or have the potential to alter bleeding. Prescription anticoagulant and antiplatelet medications, as well as over-the-counter drugs such as aspirin, are typically taken to reduce the risk of thromboembolic events, including stroke. Herbal supplements are widely used for a variety of indications, and both patients and health care practitioners are often unaware of the anticoagulant and antiplatelet effects that occur as either predictable pharmacologic effects or adverse side effects of herbal medicines. In addition, patient use of these herbal supplements is usually undisclosed to health care providers. The purpose of this literature review is to examine the mechanisms of action of drugs and herbs that alter bleeding, and to educate dental professionals as to the proper care and management of patients using these medications. Decision-making strategies, including interpretation of laboratory tests, and when to discontinue the use of these medications are discussed. Patients undergoing routine dental and dental hygiene procedures do not need to discontinue the use of anticoagulant and antiplatelet medications. However, alterations in drug use may be required for those patients undergoing invasive surgical procedures. It is recommended that herbal supplements must be discontinued 2 weeks prior to receiving invasive surgical procedures. Dental practitioners must learn to weigh the risks of discontinuing drug therapy against the potential risks to patients, and implement risk reduction strategies to minimize adverse bleeding complications associated with dental treatment.

Self-inflicted garlic burns: our experience and literature review

BACKGROUND

Throughout history, garlic has been used to treat a large variety of illnesses. One of garlic's adverse local effects is contact dermatitis.

METHODS

We present three patients treated in the Department of Plastic Surgery for suspected self-inflicted lower extremity burns.

RESULTS

The burns had unique features, not consistent with the etiology first claimed by the patients. All were soldiers with low motivation who confessed to using garlic to cause the burns.

CONCLUSIONS

Garlic application usually results in local inflammation, but, if applied under a pressure bandage, or if there is poor wound care or a secondary infection, it can cause a severe dermal reaction and a deep chemical burn. We present these cases to increase physician awareness of the characteristics of self-inflicted garlic burns, and review the dermatotoxic effect.

Potential drug–herb interaction with antiplatelet/anticoagulant drugs

This is a cross-sectional survey evaluating the use of herbal medicines in medical wards patients that may interfere with the effect of antiplatelet or anticoagulant therapy. Among the 250 patients participated, 42.4% (n=106) were taking herbs with 76 patients (71.7%) using herbs for the past 12 months. Overall, almost 31% (n=23, N=76) of patients were taking one or more of the specified herbal medicines [ginseng (Panax ginseng), garlic (Allium sativum), ginkgo (Gingko biloba) thought to interact with antiplatelet or anticoagulant therapy. The study showed that 21% (n=16, N=76) of patients co-ingested specified herbs with antiplatelet or anticoagulant therapy, of which half of them were at risk of potential drug-herb interactions. A large proportion of respondents involved in potential drug-herb interaction were elderly people (62.5%, n=5). However, more than 90% of herbal users did not disclose the use of herbal medicine to their health professionals. It is thus prudent for all care givers to be aware of the possibility of drug-herb interaction and inquire about herbal use from patients.

Herbal Supplements: Facts and Myths—Talking to Your Patients About Herbal Supplements

The use of herbal supplements in the United States is steadily growing and raises concerns about safety, efficacy, and how they affect safe patient care. The direct health risks associated with herbal supplements include hypertension, prolonged bleeding, and the potential for drug-herb interactions. These potential drug interactions are of particular concern for patients undergoing anesthesia. This article provides a review of literature on the 10 most popular herbal supplements and addresses the herbal supplements' reported use, possible adverse effect(s), patient teaching, possible drug interaction(s), and recommendations regarding discontinuation before surgery.

Hepatoprotective property of ethanolic and aqueous extracts of fluted pumpkin (Telfairia occidentalis) leaves against garlic-induced oxidative stress

Fluted pumpkin (Telfairia occidentalis) leaf is a darkish-green leafy vegetable popularly used in soup and in herbal preparations for the management of many diseases in Nigeria. In this study, the hepatoprotective property of ethanolic and aqueous extracts of T. occidentalis leaf (earlier confirmed to have a high level of antioxidant activity) against garlic induced-oxidative stress in rat hepatocytes was investigated. Oxidative stress was induced in Wistar strain albino rats by overdosing them with raw garlic (4%) for 14 days, and this caused a significant increase (P < .05) in serum alkaline phosphatase (ALP), glutamate oxaloacetate transaminase (GOT), and glutamate pyruvate transaminase (GPT), while there was no significant change (P > .05) in serum bilirubin, albumin, globulin, and total proteins. However, intubation of some of the rats fed raw garlic with 5 mg or 10 mg/0.5 mL of T. occidentalis leaf extract (ethanolic or aqueous) caused a significant decrease (P < .05) in serum ALP, GOT, and GPT when compared with rats fed raw garlic without intubation with the T. occidentalis leaf extract. Moreover, 10 mg/0.5 mL of extract was more effective than 5 mg/0.5 mL of extract, while the aqueous extracts appeared to be more effective than the ethanolic extracts in protecting hepatocytes. It could be inferred that both aqueous and ethanolic extracts of T. occidentalis leaf have hepatoprotective properties, although the aqueous extract is more effective than the ethanolic extract, which could be attributed to the higher antioxidant activity of the aqueous extract than the ethanolic extracts of T. occidentalis leaves.

Herbs and dietary supplement use in patients with stage 5 chronic kidney disease

Herbal products and dietary supplements are complementary and alternative medicine (CAM) therapies that have grown faster than any other CAM treatments. Little information is available about the use of these products in the stage 5 chronic kidney disease (CKD) population. Information on the use, safety, efficacy, adverse effects, and recommended dosages in the nondialysis population are summarized in this article.

What's Cooking with Garlic: Is This Complementary and Alternative Medicine for Hypertension?

PURPOSE

To define complementary and alternative medicine (CAM); describe one type of CAM, garlic (Allium sativum L); and discuss its effects on blood pressure as a treatment for hypertension.

DATA SOURCES

Literature review from professional journals, abstracts, natural therapy books, and the World Wide Web (Internet). Information from the following professional organizations and agencies: The World Health Organization, Agency of Healthcare Research and Quality, National Cancer Institute, National Center for Complementary and Alternative Medicine, American Botanical Council, and Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure.

CONCLUSION

Garlic is widely used throughout the world as a CAM. It is one of the most popular herbal products sold in the United States. However, while some studies have shown small positive effects in reducing blood pressure, there are insufficient scientific data to draw conclusions regarding its efficacy on clinical blood pressure outcomes. Thus, healthcare providers should be cautious in recommending this herbal product as an antihypertensive CAM.

IMPLICATIONS FOR PRACTICE

CAMs may be used by clients for a variety of conditions including hypertension. Healthcare providers must be cognizant of the use, efficacy, adverse affects, and scientific evidence concerning CAM in order to provide safe and effective practice as well as appropriate and accurate information to their clients.

Complimentary and alternative medicine use among patients starting warfarin

The use of complimentary and alternative medicines (CAM) among the UK population is on the increase. For patients requiring warfarin therapy, it is important to maintain an adequate and safe level of anticoagulation. As some forms of CAM can interact with warfarin, it is imperative that any patient considered for warfarin, is asked about their use of CAM. Our report describes the incidence and type of CAM usage among patients about to start or recently commenced on warfarin therapy attending our outpatient anticoagulant clinic. All patients attending clinic for the first time were seen by a pharmacist. A retrospective analysis of the pharmaceutical care plans for all patients seen during 2003 were analysed regarding the degree of CAM usage. Of 631 care plans reviewed, 170 (26.9%) patients were taking some form of CAM. Ninety-nine (58% of all CAM users) were taking a CAM that could interact with warfarin; the commonest forms were cod-liver oil capsules and garlic capsules. We conclude that many patients new to warfarin therapy were significant users of CAM, many of which had the potential to interact with warfarin. By taking a full drug history, potential CAM/warfarin interactions could be avoided.

Health effects of garlic

Garlic has long been used medicinally, most recently for its cardiovascular, antineoplastic, and antimicrobial properties. Sulfur compounds, including allicin, appear to be the active components in the root bulb of the garlic plant. Studies show significant but modest lipid-lowering effects and antiplatelet activity. Significant blood pressure reduction is not consistently noted. There is some evidence for antineoplastic activity and insufficient evidence for clinical antimicrobial activity. Side effects generally are mild and uncommon. Garlic appears to have no effect on drug metabolism, but patients taking anticoagulants should be cautious. It seems prudent to stop taking high dosages of garlic seven to 10 days before surgery because garlic can prolong bleeding time.

[Potential risks, adverse effects and drug interactions associated with herbal medicine in dental patients]

Herbal medicine is an increasingly common form of alternative therapy in the United States. Most herbal products are considered dietary supplements and thus are not regulated as medicines. They are marketed without prior approval of their efficacy and safety by the Food and Drug Administration (FDA). Some herbal medications have potentially harmful side effects as well as adverse interactions with conventional drugs. The adverse reactions involve all systems, age groups and severity. It is important for dentists and other health care providers to obtain adequate information as to what herbal medications their patients are taking. It is also necessary for professionals to acquire knowledge regarding herbal medications as to their use and to educate their patients about the risk-benefit and potential interactions these medications may have with over-the-counter and prescription drugs. The purpose of this article was to review the literature on the potential risks of commonly used herbal medications: Ginkgo Biloba, St. John's Wort, Ginseng, Echinacea, Saw Palmetto, Garlic, Kava and Ephedra.

Garlic: a way out of work

Two 18-year-old men were seen for second-degree burns to the dorsum of their knees, ankles, and feet. Upon investigation, it was revealed that the burns were self-inflicted and resulted from the application of crushed garlic with the intent of exemption from work. Reviews of the literature reveal that garlic-induced burns have been previously reported; however, only once before as a factitious dermatitis. The sharp demarcation line between normal and abnormal skin should suggest that a burn is not from hot liquids. Health care providers had best be advised of the side effects of natural remedies and be aware of how garlic may be abused to the advantage of an individual.

Drug-herb interaction among commonly used conventional medicines: a compendium for health care professionals

The objective of the review was to consolidate the clinical and pharmacologic aspects of drug-herb interactions to develop a compendium of information to provide prescribers with a measure of the risk of interactions, a description of the clinical consequences, and an assessment of the quality (ie, validity) of evidence. A variety of electronic databases and hand-searched references were used to identify documentation of interactions between herbal products and drugs from the most commonly used therapeutic classes. MEDLINE, Allied and Complementary Medicine Database, CINHAL, HealthSTAR, and EMBASE were searched from 1966 to the present. One hundred sixty-two citations were identified. Only 22 citations met the inclusion criteria. Using a matrix of 165 possible drug-herb interaction pairs (15 therapeutic drug classes by 11 herbal products), we identified 51 (31%) interactions discussed in the literature. Twenty-two of these 51 drug-herb pairs (43%) were supported by randomized clinical trials, case-control studies, cohort studies, case series, or case studies. The remaining interaction pairs reflected theoretic reasoning in the absence of clinical data. Most interactions were pharmacokinetic, with most actually or theoretically affecting the metabolism of the affected product by way of the cytochrome p450 enzymes. In this review, warfarin was the most common drug and St. John's wort was the most common herbal product reported in drug-herb interactions. To create a comprehensive and valid list of herb-drug interactions would require a substantial increase in research activities in this area. Improvements in the quality of methodology used are also necessary.

[Metabolic effects and drug interactions provoked by certain vegetables: grapefruit, St. John's wort and garlic]

GRAPEFRUIT: Essentially consumed in the form of juices with its bitterness helping to quench thirst, grapefruit contains not only vitamin C but also many complex antioxidizers, licopene, lemonoids and naringine. It also contains large quantities of pectin. Grapefruit juice is a metabolic inhibitor of medicinal substances that constitute an exclusive target for the CYP 3A4 isozyme and glycoprotein P in the enterocytes. Above all, it affects the drugs with strong intestinal metabolic first pass effect, phenomenon provoking the reduction of their oral bioavailability. This metabolic inhibition is manifested by an increase in the serum levels, oral bioavailability and therapeutic activity of drugs metabolized by CYP 3A4, a characteristic that may indeed be interesting for some of them, but which should be avoided for others. ST. JOHN'S WORT: (Hypericum perforatum) Also known as "herbe à mille trous" or "herbe percée" or even "herbe de Saint-Jean" in France, St. John's wort is used in several therapeutic fields: neuropsychiatry, dermatology (oleate or lipid extract) and in rheumatology. In herbal remedies and homeopathy, the flower heads are often prescribed as antidepressor in the treatment of mild to moderate depression. It also contains photosensitizing substances, which, at high dose, or during chronic use, may provoke intense dermatitis or photosensitivity. The potential occurrence of side effects with its use has led the European Agency for drug assessment and the French Medicines Agency to decree that all magistral preparations containing St. John's wort must be labeled: "Warning, risk of drug interactions". GARLIC: (Allium salivum) Originating from Asia, widespread and cultivated in Europe in kitchen gardens, garlic is used by herbalists for its diuretic, antiseptic, stimulating and sudorific properties.

[Herbal medicines--evidence and drug interactions in clinical practice]

We present an evidence-based literature review of five commonly used herbs in Denmark: St John's wort, ginkgo biloba, valerian, garlic, and ginseng. Various drug interactions are associated with the intake of some herbal medicines, and may result in many clinical conditions. We bring this to the attention of clinical practitioners. Attention to clinical practice and recommendations for discontinuation of the five herbs are given before surgery. Physicians should be aware of and report potential drug interactions and adverse effects, so as to throw more light on this subject.

The peri-operative implications of herbal medicines

An increasing number of patients are taking herbal medicines such as echinacea, garlic, ginkgo biloba, ginseng, St John's Wort, valerian, ephedra, kava, grapefruit juice and ginger. Although these herbal medications are considered 'natural' products that may have some benefits, adverse effects such as increased bleeding tendencies and drug interactions are associated with their use. Surgeons and anaesthetists may be unaware of their patients' use of these medications because it is common for patients not to disclose their use of this form of medication, and both surgeons and anaesthetists often fail to enquire about their use. Anaesthetists and surgeons must be familiar with the effects of herbal medicines and should specifically enquire about the use of herbal medicines during pre-operative assessment. Currently available data suggest that all herbal medicines should be ceased 2 weeks before surgery.

[Anterior rhinomanometry as a diagnostic test in occupational allergy caused by Liliaceae]

The Liliacea family has been implicated as a cause of occupational rhinoconjunctivitis and bronchial asthma. We report a patient who presented symptoms when he manipulated spices including garlic and onion dusts. Nasal challenge test with active anterior rhinomanometry was used for the diagnosis.

MATERIAL AND METHODS

Skin-prick tests with common inhalants, commercial spices, fresh Liliaceae and powdered spices diluted in saline solution (10 mg/ml) were performed. Immunoblot and specific IgE (CAP-Pharmacia) were determined. Control peak expiratory flow was monitored during a period at work in an area where spices were manipulated and in an area where they were transported. Nasal challenge test with garlic and onion powder was performed. The resulting nasal obstruction was measured as nasal airway resistance and was determined by rhinomanometry.

RESULTS

Skin-prick tests were positive for onion, garlic powder and fresh Liliacea. Specific IgE were positive for garlic and onion. IgE immunoblotting showed very strong bands at 14 and 40 kD with garlic extract. Nasal challenge showed an increase in inspiratory nasal resistance which was higher than 100 % of the basal value for both onion extract and garlic.

Garlic and the strabismus surgeon

Potential side-effects caused by complementary medicines are often not anticipated. A case is reported of bilateral retro-bulbar haemorrhages with elevated intraocular pressure during strabismus surgery that occurred as a result of odourless garlic tablet ingestion prescribed by a naturopath. A near-catastrophic event was averted with rapid recognition and medical treatment. This is believed to be the first such report of haemorrhaging in ophthalmic surgery induced by garlic. It is concluded that unregulated naturopathic prescribing is potentially dangerous; doctors need to ask specifically about naturopathic potions.