My son is leaving for a 6 month placement in Central & South America and his GP originally said a month ago that the prescription would be no problem but when he tried to actually get enough supplies for the trip a different GP in the practice said the limit was 3 months supplies and he would need a private prescription for the rest. Having discussed the potential problems of running out half way between Nicaragua, Costa Rica and Colombia, we have just paid £240 for a private prescription for the rest.
Added to the highly expensive gap year insurance (£380 as he had DKA the week before he bought the insurance), this essential part of his university course is becoming VERY expensive. Be warned and save up some spare stock beforehand.