Dr Clare Materia Medica

Also Known As:

Common Fennel, Garden Fennel, 

Scientific Name:

Foeniculum vulgare.

Family: Apiaceae/Umbelliferae.

People Use This For:

Dyspepsia, flatulence, bloating, loss of appetite, and for colic in infants. It is used for increasing lactation, promoting menstruation, facilitating birth, and increasing libido. 

Safety:

No concerns regarding safety, available studies validate this statement, when used orally in amounts commonly found in foods. Fennel has Generally Recognized as Safe (GRAS) status in the US.¹⁷

There is insufficient scientific information available about the safety of fennel when used in medicinal amounts.

Children: Insufficient reliable information available. Preliminary clinical research suggests that a specific multi-ingredient product containing fennel 164 mg, lemon balm 97 mg, and German chamomile 178 mg (Colimil) is safe in infants when used for up to a week.¹⁸ However, maternal consumption of an herbal tea containing fennel has been linked to neurotoxicity in breast-feeding infants.¹⁹

Lactation: Possibly Unsafe when used orally by breast-feeding mothers. Case reports have linked consumption of an herbal tea containing fennel to neurotoxicity in two breast-feeding infants.¹⁹

Effectiveness:

POSSIBLY EFFECTIVE

Colic. A clinical trial shows that breast-fed infants with colic, who are given a specific multi-ingredient product containing fennel 164 mg, lemon balm 97 mg, and German chamomile 178 mg (Colimil) twice daily for a week, have reduced crying times compared to placebo.¹⁸

There is insufficient scientific information available about the effectiveness of fennel for other uses.

Mechanism of Action:

Fennel seed is a rich source of beta-carotene and vitamin C.²⁰ It also contains significant amounts of calcium, magnesium, and iron, and lesser amounts of other metal ions. The seed contains a volatile oil.²¹ The anethole constituent gives fennel its anise-type aroma and flavor.

Adverse Reactions:

Fennel side effects have not been systematically evaluated in clinical research. One clinical trial in infants did not find a significant difference in adverse events compared to placebo.¹⁸

Overall low allergic potential except for a small subgroup that cannot tolerate celery, fennel, carrot or mugwort. These are all from the same plant family.^{R1 pp.383}

Interactions with Herbs & Supplements:

None known.

Interactions with Drugs:

Ciproflozacin (Cipro)

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of Evidence = D

Concomitant use of fennel and ciprofloxacin might reduce the effectiveness of ciprofloxacin. Preliminary evidence suggests that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. Evidence also suggests that fennel increases tissue distribution and slows elimination of ciprofloxacin.²¹

Interactions with Foods:

As above

Interactions with Lab Tests:

None known.

Dosage/Administration:

Oral: No typical dosage. However, traditionally a tea prepared from 1-2 grams of the crushed or ground fruit or seed in 150 mL boiling water has been used. The common dose of the tincture compound is 5-7.5 grams per day. Fennel should be used on a short-term basis. For colic in infants, a specific multi-ingredient product containing fennel 164 mg, lemon balm 97 mg, and German chamomile 178 mg (Colimil) twice daily for a week has been used.¹⁸

Dr Clare’s Comments:

A very well tolerated herb.  Particularly good for wind and bloating.  I have not had a patient who had to give up fennel because of side effects. Many people like the taste as it is somewhat sweet.  Fennel is native to the Mediterranean, but is now found throughout the world. 

Specific References: FENNEL

17.  FDA. Center for Food Safety and Applied Nutrition, Office of Premarket Approval, EAFUS: A food additive database. Available at: vm.cfsan.fda.gov/~dms/eafus.html.

18.  Savino F, Cresi F, Castagno E, et al. A randomized double-blind placebo-controlled trial of a standardized extract of Matricariae recutita, Foeniculum vulgare and Melissa officinalis (ColiMil) in the treatment of breastfed colicky infants. Phytother Res 2005;19:335-40.

19.  Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683.

20.  Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

21.  Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.

Also known as:

Alholva,  Bird's  Foot,  Bockshornklee,  Bockshornsame,  Chandrika,  Egypt Fenugreek,  Fenogreco,  Fenugrec,  Foenugraeci  Semen,  Foenugreek,  Greek Clover,  Greek  Hay,  Greek  Hay  Seed,  Hu  Lu  Ba,  Methi,  Methika,  Medhika,  Sénégrain, Sénégré, Trigonella, Trigonella Foenum, Trigonelle, Woo Lu Bar.

Scientific Name:

Trigonella foenum-graecum; Trigonella  foenugraecum.

Family: Fabaceae/Leguminosae.

People Use This For:

Orally,  fenugreek  is  used  for  diabetes,  loss  of  appetite,  dyspepsia,

gastroesophageal reflux disease (GERD), gastritis, constipation, atherosclerosis, hyperlipidemia, and for stimulating lactation. Fenugreek is used orally for kidney diseases, beriberi, hernia, and impotence and other male problems. Fenugreek is also used orally for fever, mouth ulcers, boils, bronchitis, cellulitis, tuberculosis, chronic    coughs, chapped    lips,    baldness,    and    cancer.

Topically,  fenugreek  is  used  as  a  poultice  for  local  inflammation,  myalgia, lymphadenitis,    gout,    wounds,    leg    ulcers,    and    eczema.

In foods, fenugreek is included as an ingredient in spice blends. It is also used as a  flavouring  agent  in  imitation  maple  syrup,  foods,  beverages,  and  tobacco.

In manufacturing, fenugreek extracts are used in soaps and cosmetics.

Safety:

LIKELY  SAFE  ...when  used  orally  in  amounts  commonly  found  in  foods.

Fenugreek has Generally Recognized as Safe (GRAS) status in the US (5). 

POSSIBLY SAFE ...when used orally in medicinal amounts (

8, 13, 16, 17, 12). 

CHILDREN: POSSIBLY UNSAFE ...when used orally; avoid using. Fenugreek tea has caused loss of consciousness and unusual body odour in children. The body  odour  may  be  confused   with   maple  syrup  disease  (12).

PREGNANCY: LIKELY UNSAFE ...when used orally in amounts greater than those  found  in  foods  because  of  its  potential  oxytocic  and  uterine  stimulant activity  (18).  Consumption of  fenugreek  just  before  delivery  may  cause  the neonate to have an unusual body odour, which could be confused with maple syrup  disease.  It does  not  appear  to  cause  long-term  sequelae  (11).

LACTATION:  Insufficient  reliable  information  available;  avoid  using.  Although fenugreek is used to promote lactation, there are no clinical studies testing its safety in mother or infant (22).

Effectiveness:

INSUFFICIENT RELIABLE EVIDENCE to RATE 

Diabetes.  Consuming  fenugreek,  mixed  with  food  during a  meal,  seems  to reduce  postprandial  blood  glucose  levels  in  patients  with type  1  or  type  2 diabetes. It may be given in combination with guar gum or by itself (15, 16, 21). Muffins  made  from  a  batter  consisting  of  foxtail and barnyard  millet,  in combination with legumes and fenugreek, do not produce a substantial increase in   postprandial   blood   glucose   in   diabetic   patients   (14).

Gastroesophageal reflux disease (GERD). Clinical research shows that taking a specific fenugreek product (FenuLife, Frutarom Belgium), 2 grams twice daily 30 minutes  before  the  two  biggest  meals  of  the  day,  significantly  improves symptoms of heartburn after one week of treatment and continuing through the 2-week study period. Fenugreek was as effective as taking ranitidine 75 mg twice daily (23).

Hypercholesterolemia. There is conflicting evidence about the use of fenugreek for  lowering     serum     cholesterol     (8,     13,     16). 

Hypertriglyceridemia.  Preliminary  clinical  research  suggests fenugreek  might lower   triglycerides   in   people   with   type   2   diabetes   (21).

More evidence is needed to rate fenugreek for these uses.

Mechanism of Action:

The applicable part of fenugreek is the seed. The active constituents include trigonelline, 4-hydroxyisoleucine, and sotolon (7, 20).Fenugreek seeds have a distinctive bitter taste and odour. Sotolon is frequently used as a flavoring for artificial maple syrup (20). Soaking fenugreek seeds overnight and washing the seeds  in  water  can  decrease  some  of  the  taste  and  odor  (13).

Fenugreek seeds contain about 50% dietary fiber and pectin and may affect gastrointestinal  transit,  slowing  glucose  absorption. About 80%  of  the  total content of free amino acids in the seeds is present as 4-hydroxyisoleucine, which appears  to  directly  stimulate  insulin  (10,  19,  20,  21). This  effect  is  glucose dependent  and  only  occurs  in  the  presence  of  moderate  to high  glucose concentrations. Some evidence suggests the seed consumption might decrease calcium oxalate deposition in the kidneys (4).

Fenugreek contains coumarins and other constituents that might affect platelet aggregation,   but   this might not be significant   clinically (7).

Preliminary research suggests fenugreek has stimulating effects on the uterus, intestine, and heart (18).

Adverse Reactions:

Orally, fenugreek  can  cause  diarrhoea,  dyspepsia,  abdominal  distention, and flatulence (2, 21). With large doses, hypoglycemia is possible (1). Fenugreek can cause  allergic  reactions  including  nasal  congestion,  hoarseness,  persistent coughing, wheezing, facial angioedema, and shock (3). The paste of fenugreek applied to the scalp can cause allergic symptoms, including head numbness, facial swelling, and wheezing (3). Consumption of fenugreek by pregnant women just before delivery may cause the neonate to have an unusual body odor, which may be confused with maple syrup disease. It does not appear to cause long-term  sequelae  (11).  This  unusual  body  odor  may  occur  in  children  drinking fenugreek tea. Loss of consciousness may also occur in children drinking tea made from fenugreek (12).

Interactions with Herbs & Supplements:

ANTICOAGULANT/ANTIPLATELET    HERBS    AND    SUPPLEMENTS:

Concomitant  use  of  herbs  that  have  constituents  that  might  affect  platelet aggregation could theoretically increase the risk of bleeding in some people (6, 7, 8). These herbs include angelica, clove, danshen, garlic, ginger, ginkgo, red clover, turmeric, and others.

HERBS  AND  SUPPLEMENTS  WITH  HYPOGLYCEMIC  POTENTIAL:

Theoretically, fenugreek might have additive effects with herbs that decrease blood glucose levels (15, 16). Herbs with hypoglycemic potential include devil's claw, fenugreek, guar gum, Panax ginseng, and Siberian ginseng.

Interactions with Drugs:

ANTICOAGULANT/ANTIPLATELET DRUGS <<interacts with>> FENUGREEK

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = B 

There is some concern that fenugreek might have additive effects when used with anticoagulant or antiplatelet drugs, resulting in increased risk of bruising and bleeding.  Some  of  the  constituents  in  fenugreek  have  antiplatelet  effects, although  these  might  not  be  present  in  concentrations  that  are  clinically significant (6, 7, 8). Some drugs with anticoagulant or antiplatelet effects include aspirin, clopidogrel (Plavix), nonsteroidal anti-infl

ammatory drugs (NSAIDs) such as  diclofenac  (Voltaren,  Cataflam,  others),  ibuprofen (Advil,  Motrin,  others), naproxen  (Anaprox,  Naprosyn,  others), dalteparin  (Fragmin), enoxaparin (Lovenox), heparin, and others.

ANTIDIABETES DRUGS <<interacts with>> FENUGREEK

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Probable • Level of

Evidence = B 

Fenugreek may reduce blood glucose levels (15, 16) and might have additive

effects  on  glucose  levels  when  used  with  antidiabetes  drugs.

  Monitor  blood glucose levels closely. Medication dose adjustments may be necessary. Some antidiabetes drugs  include  glimepiride  (Amaryl),  glyburide  (DiaBeta,  Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), and others.

WARFARIN (Coumadin) <<interacts with>> FENUGREEK

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D 

Fenugreek  might  have  additive  effects  with  warfarin  and increase  the international  normalized  ratio  (INR).  Some  fenugreek  constituents  have antiplatelet effects, although these might not be present in concentrations that are clinically significant (7, 8). Fenugreek in combination with boldo has been associated with increased INR in a patient taking warfarin (6).

Interactions with Foods:

ALLERGY TO FABACEAE: Chickpea, also a member of the Fabaceae family, has  shown  cross-reactivity  in  patients  allergic  to  fenugreek. Theoretically, patients who are allergic to other Fabaceae plants including soybeans, peanuts, and green peas might also be allergic to fenugreek (3).

Interactions with Lab Tests:

BLOOD GLUCOSE: Fenugreek can lower blood glucose and test results (15, 16).

URINE  ODOUR:  Fenugreek  can  cause  a  maple  syrup  odour  in  urine.  Avoid confusion with "maple syrup urine" disease (9).

Interactions with Diseases or Conditions:

DIABETES: Fenugreek can alter blood sugar control in people with diabetes (15, 16).   Blood   glucose   levels   should   be   monitored closely.

KIDNEY  STONES  (Nephrolithiasis):  Theoretically,  fenugreek  can decrease calcium oxalate deposition and stone formation (4)

Dosage/Administration:

ORAL: For diabetes, fenugreek 10 to 15 grams per day, as a single dose or in divided doses, with meals has been used (15, 16). A hydroalcoholic extract of fenugreek  seeds  1  gram  per  day  has  also  been  used  (21).

For hyperlipidemia, 0.6 to 2.5 grams of fenugreek 2 times daily with meals has been used. It may be used alone or in combination with guar gum and other plant fibres  (8, 16).

For  gastroesophageal  reflux  disease  (GERD),  a  specific  fenugreek  product (FenuLife, Frutarom Belgium) 2 grams twice daily, 30 minutes before the two biggest meals of the day, has been used (23).

Editor's Comments:

The taste and odor of fenugreek resembles maple syrup, and it has been used to mask  the  taste  of  medicines  (9).  Fenugreek  leaves are  eaten in  India as  a vegetable (3)

Specific References: Fenugreek

1.   Madar Z, Thorne R. Dietary fiber. Prog Food NutrSci 1987;11:153-74. 

2.  Sharma RD, Raghuram TC, Rao NS. Effect of fenugreek seeds on blood

glucose and serum lipids in type I diabetes. Eur J Clin Nutr 1990;44:301-6. 

3.  Patil SP, Niphadkar PV, Bapat MM. Allergy to fenugreek (Trigonella foenum graecum). Ann Allergy Asthma Immunol 1997;78:297-300. 

4.  Ahsan SK, Tariq M, Ageel AM, et al. Effect of Trigonella foenum-graecum and Ammi  majus  on  calcium  oxalate  urolithiasis  in  rats.  J Ethnopharmacol 1989;26:249-54. 

5.  Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances

Generally     Recognized     As     Safe.     Available     at: http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid= 78

6bafc6f6343634fbf79fcdca7061e1&rgn=div5&view=

text&node=21:3.0.1.1.13&idno=21 

6.  Lambert  J,  Cormier  J.  Potential  interaction  between warfarin  and  boldo-fenugreek. Pharmacotherapy 2001;21:509-12.