Just done a little online research and came up with this.
http://www.mskcc.org/mskcc/html/69200.cfm#HerbDrugInteractions
"Animal studies have shown moderate anti-inflammatory, cholagogic and hypoglycemic activities; however, results of studies of its diuretic properties have yielded mixed results. "
This is quite good:
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-dandelion.html
"Some modern naturopathic physicians assert that dandelion can detoxify the liver and gallbladder, reduce side effects of medications metabolized (processed) by the liver, and relieve symptoms associated with liver disease."
Interactions with Drugs
Drug interactions with dandelion have rarely been identified, although there is limited study in this area.
Dandelion may reduce the effects of the antibiotic ciprofloxacin (Cipro®) due to reduced absorption of the drug. In theory, dandelion may reduce the absorption of other drugs taken at the same time.
Dandelion may lower blood sugar levels, although another study notes no changes. Although effects in humans are not known, caution is advised in patients taking prescription drugs that may also lower blood sugar levels. Those using oral drugs for diabetes or insulin should be monitored closely by a healthcare professional while using dandelion. Dosing adjustments may be necessary.
Historically, dandelion is believed to possess diuretic (increased urination) properties and to lower blood potassium levels.
In theory, the effects or side effects of other drugs may be increased, including other diuretics, lithium, digoxin (Lanoxin®), or corticosteroids such as prednisone. However, dandelion also contains potassium and human supportive evidence is lacking.
The effects or side effects of niacin or nicotinic acid may be increased (such as flushing and gastrointestinal upset), due to small amounts of nicotinic acid present in dandelion.
In theory, due to chemicals called coumarins found in dandelion leaf extracts, dandelion may increase the risk of bleeding when used with blood thinners. Examples include warfarin (Coumadin®), heparin, and clopidogrel (Plavix®). Some pain relievers may also increase the risk of bleeding if used with dandelion. Examples include aspirin, ibuprofen (Motrin®, Advil®), and naproxen (Naprosyn®, Aleve®, Anaprox®). It is possible that dandelion may reduce the effectiveness of antacids or drugs commonly used to treat peptic ulcer disease. Examples include famotidine (Pepcid®) and esomeprazole (Nexium®).
Dandelion may interfere with the way the liver breaks down certain drugs (using the P450 1A2 and 2E enzyme systems). As a result, the levels of these drugs may be raised in the blood, and the intended effects or side effects may be increased. Patients using medications should check the package insert and speak with a healthcare professional, including a pharmacist, about possible interactions.
Be aware that many tinctures contain high levels of alcohol and may cause nausea or vomiting when taken with metronidazole (Flagyl®) or disulfiram (Antabuse®).
Although not well studied in humans, caution is advised in patients taking analgesics (pain-relievers), anti-inflammatories, or certain types of antacids or peptic ulcer agents (Pepcid® or Nexium®). Dandelion may increase the effects and toxicity of blood pressure-lowering agents or niacin if taken together.
Dandelion may also interact with cholesterol-lowering agents, such as bile acid sequestrants. Consult with a qualified healthcare professional, including a pharmacist, to check for interactions.
Other potential interactions with dandelion that are lacking human scientific evidence include anticancer agents, appetite suppressants, hormonal agents (such as estrogens), and laxatives.
Interactions with Herbs and Dietary Supplements
Interactions of dietary supplements with dandelion have rarely been published, although there is limited study in this area.
Based on an animal study, dandelion may lower blood sugar levels, although another study notes no changes. Although effects in humans are not known, caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.
Historically, dandelion is believed to possess diuretic (increased urination) properties and may increase the effects of other herbs with potential diuretic effects, such as artichoke, elder flower, or horsetail.
In theory, due to chemicals called coumarins found in dandelion leaf extracts, dandelion may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba , and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
Dandelion may interfere with the way the liver breaks down certain drugs (using the P450 1A2 and 2E enzyme systems). As a result, the levels of other herbs or supplements may become too high in the blood. In theory, dandelion may also alter the effects that other herbs or supplements possibly have on the P450 system, such as bloodroot, grapefruit juice, or St. John's wort.
Dandelion leaves contain vitamin A, niacin, lutein, and beta-carotene and thus, supplemental doses of these agents may have additive effects or side effects.
Dandelion may reduce the effectiveness of the antibiotic ciprofloxacin (Cipro®) and thus may have interactions with other antibacterial herbs or supplements.
Although not well studied in humans, dandelion may interact with anti-inflammatory agents, antacids, analgesics, hormone replacement therapy (HRT), laxatives, nondigestible oligosaccharides (such as inulin), urine alkalinizing herbs and supplements, anticancer herbs or supplements, or other antioxidants. Dandelion may also decrease dehydroepiandrosterone, dehydroepiandrosterone-sulfate, androstenedione, and estrone-sulfate levels.
Dandelion may increase the toxic effects when taken with supplements that lower blood pressure such as hawthorn ( Crataegus laevigata ). Toxic effects associated with herbs such as foxglove may increase when used in combination with dandelion.