Brief Answer:
use combination of medical and nonmedical measures as described below

Detailed Answer:
Hello.
Welcome to HCM.
This is Dr. Swarnava Dattagupta answering your query.

I have gone through your question and understand your concern.
Masturbation does not reduce penis size. Penis size varies from person to person and a moderate size is sufficient to gain sexual pleasure.
The condition you are having is called premature ejaculation. It is very common and if such patient comes to me, I suggest the following-

Distracting yourself while approaching ejaculation. It will prolong the time.
Doing kegel exercises or pelvic floor stretching exercises. Some techniques like squeeze technique are also used with questinable results.
Using drugs like dapoxetine, paroxetine, clomipramine etc. They are very useful in these conditions.

You can talk to your family doctor about the above and prescription of the above.

Hope this was useful.
Regards.

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Brief Answer:
they are prescription drugs

Detailed Answer:
Hello.
You can take medicines like dapoxetine, paroxetine, clomipramine etc as i had mentioned before. But you will need a doctor's prescription for the above. Also be relaxed, use pelvic floor exercises as advised.

Regards.

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Brief Answer:
follow the instructions given below

Detailed Answer:
Hello.
Sorry for the late reply.

The drugs I have mentioned are prescription drugs i.e. these cannot be purchased without a doctor's prescription. So you need to consult your family doctor or some other doctor to get the prescription as online prescription is not possible.
Pelvic floor exercises are tightening the pelvic muscles. Suppose when you are urinating, suddenly stop the flow. Or pretend like you are trying to stop bowel motion. It is also same as closing the anal opening forcefully by contracting anal muscles.
It is a bit difficult to understand. You can search in the internet for description if you have not understood properly.

Hope this was useful.
Regards.

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