Ashtangasamgraha 49.103

49.103

anenaiva vidhinā bhallātakasya rasaṃ gṛhītvā kevalameva māsamekaṃ prayuñjīta |

triguṇaśca kāla ityādi samānaṃ pūrveṇa |

māsi māsi varṣaśatamāyuṣobhivṛddhiḥ |

evaṃ daśamāsānupayujya varṣasahasramāyurbhavati ||

Taking the juice of bhallātaka by this very method, one should take it alone for one month. The threefold period and so on are the same as before. With each month, life increases by a hundred years. Using it in this way for ten months, one attains a lifespan of a thousand years.