i take 1000mg of ibuprophen to relieve back pain and when i do i
experience an inability to acheive an erection. is this due to the
overdose of ibuprophne or could it be due to the lower back pain?

Hi poe1966-ga,
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Short Answer:
Yes, Ibuprofen does cause Sexual Dysfunction[1,2]

Detailed Answer:
Ibuprofen works by blocking the action of a substance in the body
called cyclo-oxygenase. Cyclo-oxygenase is involved in the production
of various chemicals in the body, some of which are known as
prostaglandins. Prostaglandins are produced in response to injury or
certain diseases and would otherwise go on to cause pain, swelling and
inflammation.[3]

Medications for erectile dysfunction include phosphodiesterase
inhibitors, prostaglandins, yohimbine, and testosterone[4].

References
------------
[1] http://www.uspharmacist.com/oldformat.asp?url=newlook/files/Feat/ACF2EE4.cfm&pub_id=8&article_id=27
[2] http://health.allrefer.com/health/drugs-that-may-cause-impotence-info.html
[3] http://www2.netdoctor.co.uk/medicines/showpreparation.asp?id=1316
[4] http://www.healthyontario.com/english/channel_condition_detail.asp?diseaseid=55&channel_id=2&dowhat=accept_disclaimer

[Search Strategy]
"ibuprofen works"
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Please let me know if you have anymore questions.

-googleexpert

I have not been able to find any sexual side effects listed for
ibuprofen. Here is just one drug sheet that list the usual side
effects: http://www.netdoctor.co.uk/medicines/100001316.html

Kriswrite