Color blindness

1. Definition

Modern Definition: An inability to distinguish certain colors (usually red and green) or seeing colors differently than normal vision, often due to genetic defects in the photoreceptors (cones) of the eye.

Ayurvedic Definition: A defect of the Drishti (vision) where the vitiation of Pitta causes the patient to see everything as yellow (Pitan Pashyati), or vitiation of Kapha causes objects to appear white (Shuklan). It is a form of Drishti Dosha (visual defect) where the natural color perception is obstructed or superimposed by the color of the aggravated Dosha.

2. Etymology & Conceptual Meaning

• Pitta-Vidagdha-Drishti: Derived from Pitta (Fire humor), Vidagdha (Burnt/Scorched), and Drishti (Vision). It implies vision that has been "cooked" or distorted by excessive heat.
• Timira: Darkness or dimness. This is a progressive eye disease. In its second and third stages, as the Doshas penetrate the inner layers (Patalas) of the eye, specific color distortions (chromatopsia) occur.
• Conceptual Interpretation: Vision is the function of the Alochaka Pitta. However, if pathogenic Pitta accumulates in the eyes, it imparts its own qualities (yellow, red) onto the visual field, overriding the actual colors of objects.

3. Causes (Nidana)

Ayurveda attributes vision defects to factors that aggravate Pitta and damage the Drishti (visual apparatus).

• Dietary Causes:
  • Excessive intake of sour (Amla), salty (Lavana), and pungent (Katu) foods which aggravate Pitta.
  • Consumption of alcohol (Madya) and alkaline substances (Kshara).
• Lifestyle Causes:
  • Atapa Sevana: Excessive exposure to sunlight or bright lights, which burns the vision.
  • Divaswapna: Sleeping during the day (aggravates Kapha and Pitta).
  • Suppression of natural urges, particularly vomiting and tears, which vitiates Vata and affects the eyes.
  • Abhighata: Trauma to the head or eyes.

4. Journey of the Disease (Pathogenesis/Samprapti)

• Samprapti Ghataka (Components):
  • Dosha: Primarily Pitta (Alochaka), supported by Vata.
  • Dushya (Tissues): Rakta (Blood) and Drishti (Functional vision/Retina).
  • Srotas (Channels): Rupavaha Srotas (Channels carrying visual impulses).
  • Adhisthana (Site): The Patalas (layers) of the eye (Lens/Retina).
• Pathogenesis:
  1. Due to causative factors (like heat or spicy food), Pitta becomes aggravated.
  2. It moves upward to the head and settles in the Drishti (eyes).
  3. When Pitta lodges in the second or third Patala (inner layers), it distorts the refractive or perceptive ability.
  4. The accumulation of Pitta (yellow/red) or Kapha (white) acts like a filter, causing the patient to perceive external objects in false colors.

5. Symptoms (Lakshana)

The symptoms depend on the dominant Dosha affecting the vision:

• Pitta-Vidagdha-Drishti (Pitta-Type):
  • Pitan Pashyati: The patient sees all objects as yellow.
  • Diva Na Pashyati: Difficulty seeing during the day (Day Blindness) because the sun increases the internal Pitta heat.
  • Hrasva-Jadya: Vision is weak during the day but restored at night.
• Kapha-Vidagdha-Drishti (Kapha-Type):
  • Shuklan Pashyati: The patient sees objects as white or foggy.
  • Naktandhya: Difficulty seeing at night (Night Blindness/Nyctalopia).
• Raktaja Timira (Blood-Type):
  • Objects appear red (Rakta), dark gray (Dhumra), or black (Krishna).

6. Different Types or Classification (Bheda)

While modern medicine classifies by color axis (Red-Green, Blue-Yellow), Ayurveda classifies by the superimposed color sensation:

1. Pittaja: Yellow vision (Xanthopsia).
2. Kaphaja: White vision / Night blindness.
3. Raktaja: Red vision (Erythropsia).
4. Sannipataja: Seeing multiple colors or varicolored spots (Chitr-varna).

7. Diagnosis

• Ayurvedic Diagnosis (Roga Pariksha):
  • Prashna (Questioning): Asking the patient about the color of objects they see (e.g., "Do trees look yellow?").
  • Darshana (Observation): Examining the eye for discoloration. In Kaca (glassy eye), the lens may take on the color of the Dosha (e.g., bluish or reddish tint in the pupil).
• Differential Diagnosis:
  • Distinguished from Kamala (Jaundice), where the eyes look yellow physically, whereas in Pitta-Vidagdha-Drishti, the vision is yellow.

8. Disease Management

Management focuses on Pitta-Shamana (cooling therapies) and strengthening the Drishti (vision).

Medicines

• Triphala Ghrita: Medicated ghee used internally and externally. It is indicated for Timira and Naktandhya (night blindness/vision loss).
• Maha Kalyanaka Ghrita: Specifically indicated for Naktandhya (Night Blindness) and Timira (Visual dimness).
• Saptamrita Lauha: A formulation containing Iron, Triphala, and Licorice, specifically for Timira and strengthening vision.
• Pippalyadi Ghrita: Indicated for Timira and Naktandhya.
• Vimala Vartti: An eye salve (Anjana) used to clear vision in Timira and Kaca.

Panchakarma (Therapies)

• Tarpana: Retention of medicated ghee (like Triphala Ghrita) over the eyes. This is the foremost treatment for Timira and Drishti Dosha.
• Anjana (Collyrium): Application of medicated pastes to the eyelids to cleanse the vision. Vimala Vartti is used here.
• Nasya: Nasal administration of oils (e.g., Anu Taila or Ksheerabala) to nourish the head and eyes.
• Virechana (Purgation): Therapeutic purgation to expel excess Pitta from the body.

Diet (Ahara)

• Pathya (Beneficial): Ghee (Ghrita), milk, Triphala, honey, barley, and green gram.
• Apathya (Avoid): Sour foods, alcohol, chili, and excessive heat.

9. Prognosis

• Sadhya (Curable): Early stages of Timira or Pitta-Vidagdha-Drishti (where vision is colored but not lost) are treatable.
• Yapya (Manageable): If the condition has progressed to Kaca (where the lens/eye structure is altered), it can only be managed, not reversed.
• Asadhya (Incurable): If it progresses to Linganasha (complete blindness), it is incurable. Congenital defects (Sahaja) are generally considered difficult to cure.

10. Modern Correlations

• Chromatopsia: A condition where objects appear abnormally colored (e.g., Xanthopsia - yellow vision), which aligns with Pitta-Vidagdha-Drishti.
• Nyctalopia (Night Blindness): Correlates with Naktandhya and Kapha-Vidagdha-Drishti.
• Hemeralopia (Day Blindness): Correlates with Pitta-Vidagdha-Drishti.
• Cataract: The progression from Timira (colored vision) to Kaca (opacity) mirrors the development of cataracts, which can alter color perception.

11. References

• National Eye Institute (NEI) – Color Vision Deficiency
  Causes, types, diagnosis, and genetic aspects
  🔗 https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/color-blindness

  
  

• Symptoms, risk factors, and testing
  🔗 https://www.mayoclinic.org/diseases-conditions/color-blindness

  
  

• MedlinePlus (U.S. National Library of Medicine) – Color Blindness
  Patient-friendly overview
  🔗 https://medlineplus.gov/colorblindness.html

  
  

• Cleveland Clinic – Color Vision Deficiency
  Diagnosis and management
  🔗 https://my.clevelandclinic.org/health/diseases/8575-color-blindness

  
  

• All India Institute of Medical Sciences (AIIMS) – Ophthalmology Education
  Eye disorders awareness
  🔗 https://www.aiims.edu

  
  

• राष्ट्रीय स्वास्थ्य पोर्टल (National Health Portal – India)
  रंग अंधता / वर्णांधता
  🔗 https://www.nhp.gov.in

  
  

12. FAQ Section

Q: Can Ayurveda treat color blindness?

A: Ayurveda describes conditions like Pitta-Vidagdha-Drishti where color perception is altered (seeing yellow). While genetic color blindness is difficult to change, acquired color distortions due to eye strain or Dosha imbalance can be managed with treatments like Tarpana and Triphala Ghrita.

Q: What is "Day Blindness" in Ayurveda?

A: It is called Pitta-Vidagdha-Drishti. It occurs when Pitta (Heat) is aggravated. The patient sees everything as yellow and cannot see well during the day (when the sun is hot) but sees better at night.

Q: Is Ghee good for color vision problems?

A: Yes. Ghee (Ghrita) is the specific remedy for Pitta defects in the eyes. Medicated ghees like Maha Kalyanaka Ghrita are used to nourish the vision and clear obstructions.

Q: What is the best Ayurvedic herb for the eyes?

A: Triphala (a combination of Haritaki, Bibhitaki, and Amalaki) is the premier tonic for Netra Roga (eye diseases). It balances all Doshas and strengthens vision.