Chilli

Chilli (Capsicum annuum)

Chilli (Capsicum annuum) is a hot, circulatory stimulant that wakes everything up. Its capsaicin-rich fruits increase blood flow, warm cold tissues, and can help move stuck digestion. Used carefully, chilli is a great catalyst in formulas; it drives other herbs in, boosts metabolism, and adds a fiery kick to liniments and salves. Use with respect for sensitive folks.

Plant family

  • Solanaceae.

Parts used

  • Fructus (Fruit)

  • Semen (seeds)

Typical forms of prescription

  • Tinctures,

  • Poultices,

  • Infused oil.

  • (Not usually used in infusions)

Advise - Wash hands after topical use.

Dosage

Tincture (1:2): 1–3 ml per week.

Close-up of ripe red peppers growing on a plant with green leaves

Chilli (Capsicum annuum) - Clinical Snapshot

Primary Actions

  • Rubefacient

  • Analgesic

  • Tonic

  • Antiemetic

  • Carminative

  • Stimulant

  • Diaphoretic

  • Antiseptic

  • Styptic

  • Antithrombotic

Primary Indications

  • Poor circulation

  • Chilblains

  • Back and joint pain

  • Arthritis

  • Poor digestion

  • Flatulence

⚠️ Cautions / Safety⚠️

  • Avoid contact with eyes and sensitive areas

  • May cause skin irritation in some individuals

The Herbal Glossary

Capsicum annuum

Phytochemistry and Pharmacology

    • Action: Analgesic, circulatory stimulant, digestive stimulant.

    • Use: Capsaicin is the compound responsible for the heat in chilli peppers. It stimulates blood flow, relieves pain by depleting substance P (a neurotransmitter involved in pain signalling), and boosts metabolism. Used both internally and topically for pain relief and improved circulation.

    • Action: Antioxidant, anti-inflammatory, vascular tonic.

    • Use: Flavonoids in Capsicum help stabilise blood vessels, reduce inflammation, and enhance capillary strength, supportive in cardiovascular health and reducing oxidative damage.

    • Action: Antioxidant, tissue-protective, anti-inflammatory.

    • Use: These compounds give Capsicum its bright red-orange colour and help protect cells from oxidative stress, support vision, and reduce inflammation. They are especially beneficial for skin and mucous membrane health.

    • Action: Immune-supportive, antioxidant, collagen-forming.

    • Use: Capsicum is one of the richest natural sources of vitamin C, which boosts the immune system, supports tissue repair, and enhances iron absorption. Vital for skin healing and overall resilience.

More Chemical Constituents
Green and red chili peppers growing on a plant

Traditional use

Capsicum annuum, native to Central America, was traditionally used by the Maya and other Indigenous cultures as a powerful antimicrobial and stimulant herb. It featured in food, medicine, and ritual for thousands of years before being introduced to Europe by Spanish colonists in the late 15th century. Its pungency and therapeutic heat made it a valued remedy for infection, pain, and poor circulation.

Clinical Description

The active constituents in chilli, known as capsaicinoids, bind to TRPV1 pain receptors, producing a burning heat sensation. This causes local inflammation, followed by increased circulation and a pain-relieving effect, making it ideal for areas with poor blood flow or chronic pain.

Topically, infused capsicum oils and creams are used for joint pain, backache, arthritis, and neuralgia, bringing warmth and relief to cold, stiff, or painful areas. Internally, small doses of tincture can stimulate digestion, improve circulation to the gut, and support those with cold extremities or low vitality. It is sometimes included in formulas to reduce heavy menstrual bleeding, though it should be used cautiously due to its stimulating nature.

Its combination of circulatory stimulant, digestive tonic, and mild analgesic actions make it a valuable herb in both first-aid and long-term vitality support, especially in depleted or cold constitutions.

Cultivation/Harvesting

Capsicum annuum is a tender perennial in warm climates, but typically grown as an annual in the UK. It prefers a sunny, sheltered spot and thrives in greenhouses, polytunnels, or on south-facing patios.

Start seeds indoors in late winter or early spring, using heat to assist germination. Transplant once all risk of frost has passed. Fruits can be harvested green or red, depending on the desired potency and flavour. For medicinal use, fully ripened red fruits are preferred. Dry thoroughly and store in airtight containers, or process into tinctures or oils soon after harvesting.

Green chili pepper plant with sunlight filtering through the leaves.

Key Botanical Features of Chilli (Capsicum annuum)

Growth

  • Type: Herbaceous annual or perennial (depending on climate).

  • Size: Typically 30–150 cm (1–5 feet) tall.

  • Stem: Erect, branched, and somewhat woody at the base in mature plants.

Leaves

  • Type: Simple, alternate.

  • Shape: Ovate to lanceolate (egg-shaped to elongated).

  • Size: 4–12 cm (1.5–4.7 inches) long.

  • Texture: Smooth, slightly waxy.

  • Colour: Green, sometimes with purplish tints in some varieties.

Flowers

  • Type: Small, star-shaped, solitary or in small clusters.

  • Colour: Usually white, sometimes pale green or purple.

  • Petals: Five-lobed.

  • Blooming Period: Spring to summer.

  • Pollination: Self-pollinating, also aided by bees and wind.

Fruits (Peppers)

  • Type: Fleshy, hollow berry.

  • Shape: Varies widely – round, elongated, bell-shaped, or tapered.

  • Size: 2–30 cm (0.8–12 inches) depending on variety.

  • Colour: Green when unripe; ripens to red, yellow, orange, purple, or brown.

  • Texture: Smooth and glossy.

  • Capsaicin Content:

    • Hot Peppers: High in capsaicin (spicy).

    • Sweet Peppers: Low or no capsaicin (mild or sweet).

Seeds

  • Type: Numerous, flat, round.

  • Colour: Creamy white to pale yellow.

  • Dispersal: By animals, especially birds, immune to capsaicin.

Roots

  • Type: Fibrous root system.

  • Function: Anchors the plant and supports nutrient uptake.

Habitat & Growth Conditions

  • Climate: Warm, tropical, or temperate regions.

  • Soil: Prefers well-drained, fertile, loamy soil with a pH of 6.0–7.0.

  • Sunlight: Requires full sun (at least 6 hours daily).

  • Temperature: Optimal growth at 18–30°C (65–86°F); sensitive to frost.

  • Distribution: Native to Central and South America, now cultivated worldwide.

Sustainability/Conservation

Red chili pepper growing among green leaves.
Clusters of red chili peppers hanging outdoors.
Red chili peppers growing among green leaves.
Red chili peppers growing on green plant with dark green leaves.
Close-up of a dark green leaf with water droplets on its surface amid blurred foliage.
A bowl filled with red, yellow, and green chili peppers surrounded by white fabric with colorful patterns.

Sources

Bartram, T. (1998). Bartram’s encyclopedia of herbal medicine. Constable.

Fisher, C. (2018). Materia medica of western herbs (Rev. ed.). Aeon Books.

Hedley, C., & Shaw, N. (2020). A herbal book of making and taking. Aeon Books.

Hoffmann, D. (2003). Medical herbalism: The science and practice of herbal medicine. Healing Arts Press.

McIntyre, A. (2019). The complete herbal tutor (Revised & expanded ed.). Aeon Books.

Royal Botanic Gardens, Kew. (n.d.). Plants of the World Online. https://powo.science.kew.org/

Mills, S., & Bone, K. (2013). Principles and practice of phytotherapy: Modern herbal medicine (2nd ed.). Churchill Livingstone; Elsevier.

Barnes, J., Anderson, L. A., & Phillipson, J. D. (2013). Herbal medicines (3rd ed.). Pharmaceutical Press.

Benzie, I. F. F., & Wachtel-Galor, S. (Eds.). (2011). Herbal medicine: Biomolecular and clinical aspects (2nd ed.). CRC Press; Taylor & Francis.

Evans, W. C. (2009). Trease and Evans’ pharmacognosy (16th ed.). Elsevier.

Disclaimer: This page is for educational purposes only. Consult a qualified medical herbalist before using herbs, especially during pregnancy, when trying to conceive, while breastfeeding, for medical conditions, or with children.
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