The Compendium of Caraka 6.21.36

6.21.36

tadupatāpādāturaḥ sarvaśarīramaṅgārairivākīryamāṇaṃ manyate, chardyatīsāramūrcchādāhamohajvaratamakārocakāsthisaṃdhibhedatṛṣṇāvipākāṅgabhedādibhiścābhibhūyate, yaṃ yaṃ cāvakāśaṃ visarpo 'anusarpati so 'avakāśaḥ śāntāṅgāraprakāśo 'atirakto vā bhavati, agnidagdhaprakāraiśca sphoṭairupacīyate, sa śīghragatvādāśveva marmānusārī bhavati, marmaṇi copatapte pavano 'atibalo bhinattyaṅgānyatimātraṃ pramohayati saṃjñāṃ, hikkāśvāsau janayati, nāśayati nidrāṃ, sa naṣṭanidraḥ pramūḍhasaṃjño vyathitacetā na kvacana sukhamupalabhate, aratiparītaḥ sthānādāsanācchayyāṃ krāntumicchati, kliṣṭabhūyiṣṭaścāśu nidrāṃ bhajati, durbalo duḥkhaprabodhaśca bhavati; tamevaṃvidhamagnivisarpaparītamacikitsyaṃ vidyāt//

From that burning, the patient feels as though his whole body were being strewn with live coals; he is overwhelmed by vomiting, diarrhea, fainting, burning, confusion, fever, tamaka cough, anorexia, bursting pain in bones and joints, thirst, indigestion, aching of the limbs, and so forth; whichever region the visarpa spreads to, that region looks like extinguished coals or becomes intensely red, and it is covered with blisters resembling burns from fire; due to its swift course, it quickly reaches the vital spots; and when a vital spot is tormented, the excessively powerful vāta causes intense tearing pain in the limbs, utterly deranges consciousness, produces hiccup and dyspnea, and destroys sleep; deprived of sleep, bewildered in consciousness, and anguished in mind, he finds comfort nowhere; overcome with restlessness, he wants to move from standing to sitting to bed; heavily tormented, he falls asleep quickly, becomes weak, and wakes with difficulty; one should know such a patient afflicted by agnivisarpa to be incurable.