The duration of the numbing effect from foot numbing spray can vary depending on the specific product and individual factors. Generally, the numbing effect lasts for a relatively short period, typically ranging from 30 minutes to a few hours. It is important to follow the instructions provided by the manufacturer regarding the application and duration of the spray. Prolonged use beyond the recommended time can increase the risk of side effects and diminish the effectiveness of the product. If you require extended pain relief, it is advisable to consult a healthcare professional for alternative approaches or treatments.