How can I straight a curved penis?

See a urologist. Either penis curved downwards (cordee), or deviated can easily be corrected by an experienced recontructive urologist. An upward curve with a hard thickened area under the skin is probably due to peyronie's disease and likely caused by penile trauma. This is more complicated to treat and warrants a urologic consultation. Any combination of meds., injections, surgery or implant may be offerred.
See doc. See urologist for management of peyronie's disease.

Related Questions

Is exercise in gym affects the production of sperm or affects the sperm count? How to make curved penis straight?

Maybe... It sounds as if you may have " peyronies" disease. See a urologist but there may not be much you can do. Surgery may be an option. As far as sperm count, if your concerned it is low, also see a urologist and get that checked. Exercise does great things for us and there are strategies to increase sperm count. Good luck. Read more...