Decide based on whether your condition is likely to affect performance or communication, not on whether you can physically complete the interview.

Rescheduling has a cost, especially close to the interview, but pushing through when you cannot think or speak clearly may be worse.

If symptoms are mild and stable, you may proceed. If they are worsening, affect your voice or concentration, or could require interruptions, contact recruiting early.

Keep the message factual and concise. Ask about available alternatives rather than demanding a particular date.

The useful part for me was asking what decision the interviewer actually needed from me. That made the next step much easier.