Veerya (वीर्यम् वीर्य्यम्) refers to the energy or potency of a substance. In general it refers to energy, virility, strength, power or vigour. In the context of human beings veerya also refers to the Shukra (semen) which is believed to be responsible for regeneration and reproduction. As per Dravyagunashastram (Pharmacology and materia medica of Ayurveda) Veerya is that property of substance which enables it to perform various actions inside or on contact with human body. At some places veerya is considered to be the thermal energy of a substance.
वीरयते विक्रान्तः कर्म समर्थो भवति अनेन इति वीर्यम् |
Meaning: The strength or energy which is performing an activity via drug is Veerya (potency) of the drug
वीर्यं तु क्रियते येन या क्रिया| (Char. Samh. Sutra 26.65)
“येन कुर्वन्ति तद्वीर्यम्” (sush. Samh. Sutra 40)
Veerya of medicinal substances
(TBE)Virya describe potency of dravya or specific guna of dravya. Virya associated with gunas and considered complimentary to rasas. The Virya majorly categorized as two types (Dwividha Virya) and eight types (Asthavidha Virya) etc. cold (Shita) and hot (Ushana) Virya comes under Dwividha Virya while cold (Shita), hot (Ushna), unctuous (Snigdha), dry (Ruksha), heavy (Guru), light (Laghu), soft (Mrudu) and intense (Tikshna) Virya comes under Asthavidha Virya category. Pungent, sour and salt taste have hot potency with increasing order respectively; bitter, astringent and sweet taste are cold in potency in the same manner.
The reason and the capacity of a dravya to perform an action is Veerya(potency)2 .It is a property (karmukashaktipradayakaguna) in the dravya(drug), which makes the drug capable of exhibiting the therapeutic effectiveness in the body3 .Veerya (potency) is considered to be one among seven padartha(matter of priority) in DravyaGunaVijnana, namely Dravya (substance), Guna (attribute), Rasa (taste),Vipaka(final state of transformation), Prabhava(specificity in action) and Karma ( drug action) (TBE)
Types of veerya
Saveeryata Avadhi ॥ Shelf life of medicinal formulations
The period for which the medicinal formulations retain potency or considerable efficacy and safety is called as Saveeryata avadhi. It is similar to the concept of shelf life of food and medicinal substances. The concept of expiry date of drugs is also the equivalent concept from modern pharmaceutical science. Ayurveda acharyas have specified the period in which different types of medicinal formulations retain the maximum strength and efficacy. Since the strength, power or active energy of substance is identified as it's Veerya, this period is known as Saveeryata avadhi (Sa-intact, veeryata-strength/potency, avadhi-period). Sharangadhara Samhita from laghutrayee is the first text/treatise of Ayurveda to mention saveeryata avadhi.
For example The collected raw herb is known to loose its potency in a period of 1 year when stored as it is. Some formulation methods enhance the potency and increase the saveeryata avadhi. Specifically fermented preparations in Ayurveda formulations known as Asavas and arishtas do not loose their potency over years. In fact those are considered to be more effective if stored for long time.
Significance of Veerya
नावीर्यं कुरुते किञ्चित् सर्वा वीर्यकृता क्रिया||६५|| Char. Samh. Sutra 26.65)
- Sharangadhara Samhita (Prathamakhanda Adhyaya 1 Sutra 51-54)