Merlin is called ibuprofen suspension, which can be used to treat all kinds of colds, including the common cold or flu-induced fever, as well as general pain, such as headache, toothache, joint pain, menstrual pain and so on. The duration of action of Merlin suspension can last up to eight hours, which means that if you take it once to reduce fever, you will not get fever again within eight hours. If there is a fever, the next dose should be given at an interval of eight hours if possible, that is, up to three times a day. Because too much and too frequent administration of Merlin may bring obvious side effects, including irritation of the gastrointestinal tract, nausea, vomiting, abdominal pain, including serious damage to the mucous membrane of the stomach and even ulcers, it is clearly stated in the instruction manual that Merlin should be given once every eight hours to reduce fever or relieve pain, no more than three times a day, and no more than three days for continuous use to reduce fever and no more than five days to relieve pain. It should not be used continuously for more than three days to reduce fever and not more than five days to relieve pain. Therefore, giving it once at an interval of three hours may not be appropriate because it does not bring out the long-lasting effect of Merlin and also increases the potential adverse effects.