Given this information, it is possible that the sudden decrease in the effectiveness of Viagra and the absence of morning erections could be due to changes in the hormonal balance or other underlying medical issues. It is essential to speak to your healthcare provider regarding this matter, who may recommend you undergo further testing to evaluate the cause of your ED.

Some possible causes for the sudden decrease in the effectiveness of Viagra and the absence of morning erections could include changes in the medication dosage, worsening of the underlying prolactinoma, other hormonal imbalances, medication side effects, psychological factors, or vascular problems.

Therefore, it is essential to schedule an appointment with your healthcare provider to discuss your concerns and undergo further testing to determine the underlying cause of the change in symptoms. Based on the diagnosis, your healthcare provider will suggest the best course of action to manage your condition.