Fenglan is an oral aphrodisiac, which usually takes effect within 30 minutes and lasts for about 4-6 hours. If you need to have further sex within 4 hours after taking Fenglan, it may still have some effect, but the specific situation varies from person to person and depends on many factors, such as individual differences and dosage.

It should be noted that Fenglan is a prescription drug, which should be used under the guidance of a doctor and cannot be abused by itself.