I wouldn't do that if I were you. Once you stop strattera, going back on it will give you all the side effects you had when you started the drug. Strattera is not like Ritalin or Adderall, you cannot just start and stop it.
Honestly don't know, I think since this drug is suppose to build up - you are not suppose to be cutting out during the building period.Tav- Yes, you can go off your medication on weekends but you may not get the full desired effects of the drug. According to Eli Lilly (the company who makes Strattera) the drug takes full effect in 1-2 hours after taking it by mouth, peaks at approx 5-6 hours and is fully excreted in about 21-22 hours. And there is a long list of male sexual side effects although they are rare. Impotence, abnormal orgasam, no orgasam , or difficuty urinating You can check it out here if you want.
http://pi.lilly.com/us/strattera-pi.pdf
But ditto on what Cheeky said. Ask the MD about getting on another med. Maybe go back to Wellbutrin???
Well,
It's been many years since I was such a stud that I had to worry about going without sex on the weekdays and settling for only the weekends. If you are able to maintain relationships well enough that you are having sex multiple times a week your ADD does not seem to be too bad of a problem for you! 
I have been on Straterra for alost 3 months now and have not had any sexual side effects at all. The worst side effects I have had is some drowsiness about 3-4 hours after taking it and some headaches when I was upping doses.
It seems like most people on this site have had really bad experiences with Straterra.