What goes wrongBoys - your penis hurts, especially when you pee. Girls - it can hurt when you pee. It is also possible to get a discharge from the penis or vagina, amongst other problems.
It's caused by
Having sex with someone who's carrying various bugs like gonorrhoea, chlamydia or trichomonas. The bugs hang round for a bit and then make the lining of your urethra (the tube through which you pee) inflamed and sore. Occasionally it may just be a bit of inflammation and not due to a bug.
How not to get it
Don't have sex with someone carrying a bug. But as it's almost impossible to know who has or who has not got an infection so be safe and use a condom.
What to do
Boys - it's very important to get this sorted as soon as possible. If you pass chlamydia on to another girl, it could make her unable to have babies. Go to your doctor or to a clinic ;and get some antibiotics for both of you. Girls - get this sorted urgently as it may interfere with you having babies. Head for your doctor or a clinic and get antibiotics yourself.
For more info - www.fpa.org.uk