Botanical name

Allium sativum L.

Family

Amaryllidaceae

Information about the plant

Central Asia is considered the home of garlic, but the plant has been cultivated for a long time and is now grown in almost the entire world, especially in the Middle East. The European demand for garlic is covered by crops in southern Europe.

The long tradition as a cultivated crop is expressed in the epithet sativum (Latin "sativus" = cultivated, planted, sown). The etymology of the genus name Allium is unclear; it may be derived from the Latin "olere" (= to smell), which refers to the distinctive odor of the Allium species, including garlic, onion, wild garlic, and chives. The German name “Knoblauch” is associated with the Old High German 'klobo' (= split stick, clove), which means “split leek”. This refers to the garlic bulb made up of individual cloves.

In contrast to onion (Allium cepa), garlic is not a bulb with nested layers. Its tubular-shaped, separate, white leaves grow side by side around the compressed axis. Each leaf encloses 3 to 5 "cloves". These closely wedged pieces have slightly angular, curved sides. At the top of the bulb, it is covered with rootlets around the elongated-ovoid head. The edible part of a clove consists of a fleshy lower leaf of the rhizome (underground stem portion), which surrounds the tubular bud. The white and red paper-like encasing of the clove must be removed before use. Major and minor bulbs are also encased together in several dry-skinned whitish lower leaf sheaths, giving the impression of an "onion". The plant is a perennial that grows 25 to 70 cm tall with an erect, rigid stem, leafy up to the middle with flat, broad-linear, pointed foliage. The flowers are on long stalks, but mostly in the bud stage; the petals are reddish or greenish white.

Medicinally used parts of plants (herbal drug)

The dried cloves are used in the form of powder (garlic powder - Allii sativi bulbi pulvis).

Garlic is imported from the Mediterranean countries and from China.

Constituents of the herbal drug

The fresh garlic clove contains the odorless alliin [(+)- S-allyl-L-cysteine sulfoxide]. Upon cutting and drying, contact with the garlic enzyme alliinase produces allicin (allyl 2- thiosulphate propane). This gives the pleasant smell of fresh garlic but then turns spontaneously into strong-smelling volatile sulfur compounds. The alliin-alliinase system must remain as intact as possible during the production of the drug, which is achieved through the fast and gentle drying of the bulb.

Quality of the drug

The quality of garlic powder (Allii sativi bulbi pulvis) is specified in the European Pharmacopoeia (Ph. Eur.), as is the quality of Allium sativum for homeopathic preparations.

Medical applications

Recognised medical use

The HMPC has classified garlic bulb as a traditional herbal medicinal product (see “Traditional use”).

ESCOP: Preventive against atherosclerosis, also for elevated blood lipid levels that cannot be sufficiently controlled by dietary measures; supportive for elevated blood pressure; infections and catarrhs of the upper respiratory tract.

Traditional use

The HMPC has classified garlic bulb as a traditional herbal medicinal product (Article 16a of Directive 2001/83/EC). Based upon long-standing use, garlic bulb can be used preventively against atherosclerosis and to relieve cold symptoms.

Herbal drug preparations in finished dosage forms

• Garlic bulb powder in capsules and tablets
• Garlic oil macerate in capsules

Dosage

Finished product: see patient information leaflet.

Fresh garlic bulb: Average daily dose 4 g. It is not advisable to prepare a tea infusion, as the alliin contained in garlic is hardly soluble in water and, therefore, hardly passes into the tea; in any case, it would then spontaneously transform into unpleasant-smelling sulfur compounds during preparation.

Preparation of a tea

Not applicable.

Notes

Consumption of garlic and garlic preparations leads to changes in body odor and breath.

There is no evidence of risks during pregnancy and lactation. However, garlic substances pass into breast milk. In children and adolescents, the clinical symptoms of arteriosclerosis are not relevant.

Side effects

Rarely, gastrointestinal complaints or allergic reactions.

Interactions

There are no entirely clarified references to a possible strengthening effect of concomitantly ingested anticoagulants (Marcurmar etc.) and blood pressure-lowering drugs. Also, there is no clarified indication of a possible weakening effect on HIV protease inhibitors such as Saquinavir/Ritonavir.

References

Herbal drug monographs

HMPC (2020, 2021), ESCOP (2019), WHO (Vol. 1, NIS)

Further literature

Commentary on the European Pharmacopoeia (Garlic powder, No. 1216)