I am 49 years old. For some time I have problems in sustaining my erection. I am taking 5 mg amplodipine for my hypertension treatment every morning. My blood pressure is usually 80-90 mmHg diastolic and 120-135 systolic. Slight use of alcohol has a lowering effect, so that SP goes down to 105-110 and DP to 65-75. A couple of days ago I have tried to take sildenafil just 25 mg just one hour before having sex for the first time in my life. I had no alcohol. After half an hour or 45 minutes my blood pressure went up 110/170 mmHg and heart beat 96 (normally I have 55-60). Which worried me a lot, may be panic. Having rest for a while It dropped to 105/145 mmHg and we had sex with my wife. The erection problem was over, I had an sutaining erection and ggod sex. After the sex I took a reading of 84/125 mmHg. Everything was normal. Is this a serious side effect or jus temporary reaction of the body to the first usage. Can It happen again?