While drugs like Viagra can certainly help men regain their erections, they won't make them any happier, a new US study claims.

PDE5 inhibitors such as Viagra, which work by relaxing blood vessels, help tackle the physiological side of erectile dysfunction, or ED, but they don't address psychological causes of impotence, LiveScience reports. The study, which examined 40 clinical trials, was published November 21 in the Journal of Sexual Medicine.

"It's simplistic to think that fixing an erection issue would solve relationship issues," said researcher Dr. Andrew Kramer of the University of Maryland Medical Center. "Happiness is very complicated. A lot of couples still need additional therapy."

Other issues affecting impotence include depression, anxiety, and relationship problems, as well as alcohol and drug use.

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  • 'Hold On, Let Me Get That'

    Really, you don't have a better time to answer your latest text message or email? If you're planning a romantic night with your partner, put the phone away.

  • 'I Need To Turn Off The Light. Now.'

    Yes, being in the dark sets the mood, but randomly telling your partner halfway through sex you don't want to see his or her face is not cool.

  • "Sorry, What's Your Name Again?"

    Do your homework. It may not matter to everyone, but it's just common courtesy to remember the person's name you're sleeping with.

  • 'I'm Hungry'

    Sex is not the time to be thinking about a greasy slice of pizza. And if you are, don't ruin the mood.

  • 'Do You Mind If I Instagram This?'

    Don't even think about it.

  • 'Can You Hurry Up?'

    Not everyone works on the same schedule and telling someone to "hurry up" can make them feel super uncomfortable.

  • 'What IS That'

    Just don't do it.

  • 'My Ex Was Better'

    Not only is it rude, but bringing up your ex (at any time) is never a good idea.

  • 'Oh No, I'm Going To Fart'

    OK, we get it, it's natural, but it's the worst turn-off.

  • 'Does This Count As A Date?'

    Can we say awkward?

  • 'You Have To Look Into My Eyes'

    It's a nice thought, but if you HAVE to do it, then it gets a little creepy.

  • 'What's That Smell?'

    For anyone who is nervous or body conscious about having sex, commenting on the smell of their, um, odour isn't appropriate. If it's a regular issue, bring it up with your partner another time.

  • "Are You Done Yet?'

    People, this isn't a race. Go at your own pace and don't make your partner feel like they're doing a bad job.

  • 'Remember That Fight We Had Yesterday?'

    Again, not the right time.

  • 'Can My Dog/Cat/Bird/Pet Watch?'

    Unless both of you are cool with your pets in bed, bringing it up during sex might make things a little bit more uncomfortable.

  • 'Remember How I Said I Was On The Pill...'

    Uh, yeah. This probably won't end well.

  • 'Do I Look Fat?'

    It's bad enough mentioning your partner's weight, but forcing them to make a comment on yours is even worse.

  • 'Sorry, I Fell Asleep For A Second'

    And yes, this is just as bad as, "Wake me up when you're done."

  • 'This Used To Be Fun'

    Way to kill the mood. Instead of making your partner feel inadequate, maybe you should try a new position to spice things up.

  • 'I'm Seeing Someone Else/Can We See Other People'

    If you're not actually trying to make your partner cry, don't try this.

  • <strong>NEXT ----> Ramp-up to Grey Cup 101</strong>

  • <strong>NEXT -----> Stampeders Vs. Roughriders Western Finals</strong>

  • Saskatchewan Rough Riders Tyron Brackenridge breaks up a pass intended for Calgary Stampeders Brad Sinopoli during second half CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Calgary Stampeders quarterback Drew Tate tries to pass the ball while going to the ground against the Saskatchewan Rough Riders during second half CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Saskatchewan Rough Riders Paul Woldu celebrates the teams win over Calgary Stampeders in CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Saskatchewan Rough Riders Geroy Simon celebrates with the team Calgary Stampeders during second half CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Saskatchewan Roughriders' fans celebrate the win over the Calgary Stampers during CFL Western Final action in Calgary, Alta., Sunday November 17, 2013. THE CANADIAN PRESS/Larry MacDougal

  • Saskatchewan Rough Riders Kory Sheets celebrates the Riders win over Calgary Stampeders in CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • A Calgary Stampeders fans braves the cold in a game against the Calgary Stampders in first half CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Saskatchewan Roughriders' coach Corey Chamblin has a bucket of water poured over him as the team celebrates winning the CFL West Final in Calgary, Alta., Sunday, Nov. 17, 2013. The Saskatchewan Roughriders beat the Calgary Stampeders 35-13. THE CANADIAN PRESS/Jeff McIntosh

  • Saskatchewan Roughriders' Tyron Brackenridge, left, blocks Calgary Stampeders' Brad Sinopoli, during second half CFL West Final football action in Calgary, Alta., Sunday, Nov. 17, 2013. THE CANADIAN PRESS/Jeff McIntosh

  • Saskatchewan Rough Rider Jock Sanders (2) tries to break away from Calgary Stampeders tacklers during first half CFL action in Calgary on Sunday, November 17, 2013. (CFL PHOTO - Mike Ridewood)

  • Saskatchewan Roughriders' quarterback Darian Durant, takes a snap during first half CFL West Final football action against the Calgary Stampeders' in Calgary, Alta., Sunday, Nov. 17, 2013. THE CANADIAN PRESS/Jeff McIntosh

  • Saskatchewan Roughriders' Kory Sheets, right, gets away from Calgary Stampeders' Cordarro Law during first half CFL West Final football action in Calgary, Alta., Sunday, Nov. 17, 2013. THE CANADIAN PRESS/Jeff McIntosh