For a person with a known kidney/ureteric stone, intermittent flank or back pain can be renal colic, but new pain should not automatically be assumed to be from the stone.

At night: use a warm pack on the sore area, rest in a comfortable position, and drink normally to thirst. Do not force large volumes of water during active severe pain or vomiting.

Seek urgent care now if pain is severe or unrelieved, fever/chills, vomiting or inability to keep fluids down, burning urine with feeling unwell, very little/no urine, a single kidney, pregnancy, or known kidney impairment. A blocked infected kidney is an emergency.

If the pain keeps returning, they need prompt review by their urologist or clinician to check stone size/location and whether it is obstructing. NSAIDs are generally more effective than opioids for renal colic, as summarized in Campbell-Walsh Urology (Pain Management section).

Not universally. NSAIDs are usually first-line for confirmed renal colic, because they reduce ureter inflammation and pain.

But you are right that they should not be given if there is a risk they could worsen kidney function or cause bleeding, including:

In those cases, paracetamol/acetaminophen is generally the safer initial option, but persistent or colicky stone pain should be assessed by a clinician. Hospital treatment may use IV paracetamol, with an opioid only when necessary and supervised.

So: a stone itself is not a reason to avoid NSAIDs, but impaired/at-risk kidney function or the above factors is. Campbell-Walsh Urology specifically cautions against NSAIDs in renal insufficiency. NICE guidance likewise recommends an NSAID first-line only when not contraindicated.