Brief Answer:
you need evaluation of present conditions and medications...

Detailed Answer:
Hi XXXX,

Thanks for writing to us.

I can understand your concern.

I would like to tell you that masturbation does not cause any problem related to penis or sex.

From your narration it seems that you are suffering from erectile dysfunction and may be from premature ejaculation.

Erectile Dysfunction(ED)- Penis does not get erection sufficient to do successful intercourse in at least 75% attempts of sex.It just becomes loose before reaching to climax. And,

Premature Ejaculation(PME)- Penis loses erection with ejaculation before female partner reaches to orgasm.

Can you clarify which of these two conditions are you suffering from?

At age of 31 , most of the males have sex problem mostly psychological origin.However following factors indicate that you may have physical component also in your problem.

Height 170 cm and weight 118 KG suggest obesity. Obesity itself is a modern disorder which leads to many health hazards.Your Body Mass Index(BMI) is 40. At present your weight should not be more than 72 kg considering your age and height.If you can reduce your weight , it will not only help in sexual problem but will help in many other aspects of health.

High blood pressure also affects penis erection. Your blood pressure should be under control with medicines.Sometime medicines to treat hypertension also can cause sexual problem. We need to check it.

To get good erection with medicines 5-PDE inhibitor group of medicines are useful. Among them tadalafil is preferred in patient with hypertension.It should be taken just before 2 hours of intercourse on required basis.
One medicine cum vitamin product Tetrafol Plus has helped in some patients. It should be taken twice daily for at least 15 days to see the effects. If improvement is there , you can continue it for 2 months.

To make erection long lasting clomipramine or paroxetine is useful.

In both ED and PME ,some sex counseling, couple counseling and sexual techniques like ' Stop and Squeeze', 'Master & Johnson' can help.

For all above approaches for treatment you should consult a psychiatrist/qualified sexologist in personal. Please go with your current medicines for blood pressure and if any other medical records if you have.
Psychiatrist can help you in weight reduction, Sex counseling and prescription of medicines for ED and PME after detail history and thorough examination.

Hope I have answered your query, I will be happy help further.

Regards,
Dr.Chintan Solanki.

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