Tamiflu (oseltamivir) is often used in patients diagnosed with flu or those who are most likely to fall ill. It can prevent the symptoms of sore throat, muscle aches, runny or stuffy nose, headache, or help to relieve them faster when they are already present. Tamiflu is sold in two forms – as a capsule and liquid. Do not take more of this medicine than prescribed and make sure you measure your dose with a special measuring spoon (usually provided when you purchase the liquid form). If you do not have such a spoon, ask your pharmacist for one. Being allergic to the active ingredient of this drug is a direct contraindication for taking it. Tell your doctor that you are allergic to oseltamivir and you will be most likely recommended another medicine that will be beneficial for you without dangerous health effects.