Eyebright: Benefits, Dosage, and Side Effects

Eyebright (Euphrasia officinalis), also known as meadow eyebright and red eyebright, is native to Europe, particularly the United Kingdom. It thrives in open grasslands or meadows, particularly in temperate climatic zones. Although the bulk of eyebright marketed originates from Europe, it has also been discovered in Northern and Western Asia, as well as North America.

Eyebright is an annual plant.

• It is a tiny shrub that grows two to eight inches tall and grows best in regions with good soil.
• It features deep-cut leaves and tiny, variegated blooms.
• Its flowers may be purple or white and its stem is slender and rigid.
• Its leaves are nearly half an inch long by one-fourth inch broad, with four or five teeth on each side.

Eyebright is a hemiparasitic plant—it takes nourishment by attaching itself to other plants and can perform photosynthesis (the process of making food). As the plant is attached to host plants, harvesting it may be difficult. Summer is the best season to harvest the plant because it is in full bloom. 

Although it grows best in broad fields, eyebright may also grow on rocky soil. However, in these conditions, the plant is usually barely an inch tall, and the stem does not branch as extensively as it would in an open meadow or grassland.

Extracts of eyebright leaves, stems, and flowers contain useful chemicals such as:

• Flavonoids, including luteolin and quercetin
• Iridoglicozoids (aucubin)
• Tannins and phenolic acids, which have anti-inflammatory and anticatarrhal (removes mucus) properties

Tea and dietary supplements made out of eyebright plant parts have been used as herbal medicines for centuries. 

The flavonoids in eyebright inhibit the release of histamine, a chemical substance that causes allergy symptoms such as a runny nose and watery eyes.

1. Reduces eye inflammation:
   • When used as a cool eye compress, eyebright tea may be effective for ophthalmia, blepharitis, stye, and other eye irritation. 
   • Eyebright tea is made with one teaspoon of properly cleansed eyebright herb boiled in one and a half cups of water for 10 minutes.
   • Allow cooling after draining the leaves using a fine sieve or cotton cloth. 
   • Use a tiny cotton pad dipped in it as a compress three to four times a day.
2. Treats conjunctivitis and cataracts:
   • A study reported that 81.5 percent of people with conjunctivitis showed complete recovery after using eyebright eye drops. 
   • Eyebright tincture wash may help treat cataracts. 
   • To relieve symptoms, mix five to eight drops of this tincture in two glasses of lukewarm water and wash the afflicted eyes with the solution every four to six hours.
   • However, do not take this medicine for an extended period and always consult a competent herbalist before use.
3. Relieves cold, sinusitis, and seasonal allergies:
   • Eyebright is said to be a potential cure for allergies and respiratory symptoms. 
   • The herb's natural astringent-tannins and anticatarrhal properties may help minimize mucus secretion during colds and flu. 
   • Eyebright's flavonoids and other anti-inflammatory components may aid in the treatment of:
     • Seasonal allergies
     • Coughs
     • Colds
     • Chest congestion
     • Stuffy nose
   • Make eyebright tea by steeping the eyebright teabag in a hot cup of water for five minutes and drinking it two or three times a day. 
   • When using dried eyebright leaves, add one teaspoon of dried leaves to one cup of hot water. 
   • Allow it to soak for five to seven minutes before straining out the leaves. Add honey for sweetness.
4. Treats other upper respiratory tract conditions:
   • Eyebright can help treat upper respiratory tract conditions such as:
     • Common cold
     • Hay fever
     • Sore throats
     • Hoarseness
   • This herb can help reduce bronchial and pulmonary irritations caused by measles. 
5. Reduces acne and skin irritation:
   • Antibacterial and astringent characteristics of eyebright aid in the healing of acne and irritated skin. 
   • Applying cool eyebright tea, poultice (a paste made of herbs), or tincture to the affected area can help treat acne outbreaks.
   • Crush some fresh eyebright leaves and flower petals to make the poultice, then apply it directly to the acne and leave it for 20 minutes before wash. Practice this every night before bed.
   • Dab a cotton ball in cold steeped tea or a combination of four to five drops of eyebright tincture in cold water and apply to the affected regions gently.
   • Alternatively, mix five to six drops of eyebright oil with face moisturizer and apply it to the skin and leave overnight.
6. Promotes skin wound healing:
   • The plant is used as an astringent to help in the healing of skin wounds.
   • A cool eyebright poultice might aid in skin tightening and wound healing.
7. Protects the liver:
   • Some claim that the presence of aucubin in this plant aids in the reversal of liver damage and curing jaundice. 
   • The plant promotes good liver function by cleansing and detoxifying the blood. 
   • Aucubin has hepatoprotective properties and is effective against the hepatitis B virus.
8. Improves memory:
   • Beta-carotene is abundant in the eyebright. 
   • Researchers found that men (65 years and older) who took beta-carotene supplements for 18 years showed improvements on verbal memory tests than the placebo group. 
   • Mix two tablespoons of dried eyebright powder, two tablespoons of fennel seeds, one teaspoon of honey, and half a teaspoon of minced mace. 
   • Take half a teaspoon of this mix with water or fruit juice every morning to improve memory. 
   • Alternatively, drinking one cup of eyebright tea every day can help prevent memory loss and safeguard intellect.

The dosage of eyebright extracts depends on the type of extract.

• Dried herb: 
  • Take two to four grams by infusion three times a day.
• Liquid extract:
  • Prepared in 1:1 ratio with 25 percent alcohol solution.
  • Take 2 to 4 mL three times a day.
• Tincture:
  • Prepared in 1:5 with 45 percent alcohol solution.
  • Take 2 to 6 mL three times a day

The dosage is determined by the severity of the condition. A simple poultice can be used to treat blepharitis, conjunctivitis, and eyestrain. To complement the exterior therapy, brew tea. 

Some people feel that taking an eyebright herbal supplement may help them maintain or improve their vision. Consult the doctor before using eyebright for any issue.

Most individuals may not have serious issues while taking eyebright orally. However, using it directly on the eyes is probably dangerous and not suggested because there is a high possibility of contamination or eye infection. 

The most common side effects associated with the use of eyebright tincture include:

• Nausea
• Confusion
• Tearing of the eyes
• Itching of the eyes
• Headache
• Difficulty breathing
• Redness of the eyes
• Sneezing
• Vision issues 
• Toothache 
• Sweating 
• Constipation
• Coughing
• Insomnia (difficulty sleeping)

Contraindications of eyebright

• Pregnancy and breastfeeding: 
  • Avoid using eyebright during pregnancy or lactation because there are currently insufficient solid data to support its safety.
• Diabetes: 
  • Eyebright may lower blood sugar levels in some people. 
  • Practice caution while taking eyebright, and look out for symptoms of low blood sugar.
  • Monitor blood sugar levels while using eyebright, especially if you have diabetes.
• Surgery: 
  • Eyebright may interfere with blood sugar regulation during and after surgical procedures. 
  • Discontinue the use of eyebright at least 15 days before a scheduled operation.