Sharad is the season the texts single out as the one people misjudge, and the mechanism is worth understanding because it is counter-intuitive.
Through the rains, the body was cold, damp and low. Pitta was quietly accumulating the whole time — sanchaya, the silent stage. Then the clouds clear, the sun comes back hard onto a body that has spent two months adapted to damp and dimness, and that banked Pitta breaks out. Charaka's image is exact: a body accustomed to cold, suddenly met with heat.
So autumn's signature complaints are heat complaints, arriving in weather that feels pleasant. Skin eruptions and rashes. Acidity, reflux and burning. Loose stools. Red, hot or gritty eyes. Headaches behind the eyes. Irritability with a short fuse. Bleeding tendencies — nosebleeds, heavy periods, bleeding gums. If any of those show up around now, this is the season's fingerprint, not a coincidence.
And the classical mistake follows directly: the air is cooler, appetite has returned after a month of nothing, so people eat as though winter has arrived. It has not. Heavy, oily, sour, salty and fermented food into an aggravated Pitta is the single most reliable way to make October unpleasant.
The sandhi rule, one more time. A week to taper the monsoon's warm, sour, salty regimen; a week to bring in autumn's sweet, bitter and cooling one. Both moves matter — dropping the monsoon's warmth abruptly is as much a mistake as clinging to it.
One beautiful detail from the texts. Water in Sharad has a name of its own — hamsodaka, swan water: water heated by the day's sun and cooled by the night's moon, considered the purest of the year and non-aggravating to any of the three doshas. The modern version is unglamorous but real — this is a good month to drink plenty of plain water, at room temperature, and to leave the ice alone.