Hello dear Understand your concern Following are the causes of your problem Fatigue, stress, relationship issues, performance anxiety, alcohol consumption, diabetes, obesity, tobacco use, enlarged prostate gland. So please do full health check up(Glucose level, lipid profile, Hormonal profile) to exclude above causes. Take following advice 1. Start exercising, losing weight, stopping smoking and alcohol if you are taking 2. Tablet viagra 50 mg taken about one hour before sexual activity. It may be taken between 30 minutes and four hours prior to sexual activity. maximum dose of 100 mg daily or reduced to 25 mg daily. Do not use more than one time daily 3. Testosterone Replacement Therapy after consultant with doctor. 4. drug : paroxetine 10 mg 30-40 min before sex 5. Alprostadil urethral suppository-By applicator to insert the suppository into yourpenile urethra, erection usually starts within 10 minutes and lasts between 30 and 60 minutes. 6. Do discussion with your partner that help in gaining psychological trust Following advice are also useful: 1. Distract your mind from sexual stimulation 2. withdrawing the penis altogether, 3. purposefully ejaculating before sexual intercourse 4. using more than one condom 5. use squeez technique to reduce excessive arousal Hope this may help you. Take care