Brief Answer: Loose weight,Do duplex ultrasound Detailed Answer: Hello sir, Nice to meet you here, The reason behind the shrinkage of penis in old age is due to , decreased flow of blood to the penis parts,decrease in testosterone level and gaining weight {accumulation of abdmonial fat results in the apparent shrinkage of penis}. I also like you get examined to rule out peyronie disease and corporal fibrosis which are common in old age. Duplex ultrasound helps to find any blocks in the blood flow to the penis. It may be needed. Try to loose weight if you are over weight or near obese. You can also try FDA approved vacuum devices under doctors prescriptions . Avoid excess usage of medication for erectile purpose in old age (if you been using it). Hope this helped you. Feel free to contact me again anytime for any clarification Take care dr.Surendiran Gaj.

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