Doubling the dosage of Vidalista 40mg may increase the risk of adverse effects, including headache, dizziness, flushing, nasal congestion, and gastrointestinal discomfort. Serious side effects such as priapism (prolonged erection) and sudden vision loss are rare but require immediate medical attention. Patients should be aware of these potential risks and consult their healthcare provider before adjusting their medication dosage.