When my son Ryan, 4yrs old, spikes a fever of 101 or higher our endo has us triple his daily dose. She has us use his normal dose (1/2 tab, 1/2 tab, 1 full tab; 2.5, 2.5, 5); which is 2 full tabs a day and triple so that he would get 6 full tabs a day and administer it by 3 times a day so that he would get 2 full tabs each time. If he had already received say 1/2 tab and then two hrs later spiked a fever I would give him another 1 1/2 tab and then at the next scheduled time I would give him 2 full tabs. The only way I wouldn't do this is if he were due shortly for his next dose then I would just give him the two tabs at his next dose. Of course I also administer motrin. There are times however, where the fever goes away and I give the increased dose for the 2 time and I don't for the 3rd because the fever stayed down. You have to decide what works for your child and see how your endo feels. Our endo has never advised to just double we always triple. Hope this helps