Is money earned from trading considered permissible (halal) or impermissible (haram) if it is for the purpose of buying a car to avoid headache-inducing allergies caused by public transportation, especially since this headache negatively affects my university studies in medical school?

The nature of the transaction from which the profit was gained has not been clarified. Most trading transactions typically involve Sharia (definition) violations such as leverage, Contracts for Difference (CFDs), and options.

If the trading is permissible according to Sharia, then there is no objection to purchasing a car with the profits. However, if it is not compliant with Sharia, then the profits are unlawful, and it is not permissible to buy with them. Rather, one must dispose of them by spending them on public welfare and charitable causes.

The need for a car is not an excuse to engage in forbidden trading, as this does not constitute a necessity. "And whoever fears Allah, He will make for him a way out and will provide for him from where he does not expect." (Quran 65:2-3). And whoever fears Allah and relies upon Him, He will provide him with lawful sustenance and suffice him in what worries him.