A number of factors can affect a patient's proper Imodium AD® dosage. A doctor will usually examine the patient in order to determine the proper dose for that individual's current gastrointestinal distress, though most patients will take a standard dose of this drug. Factors such as age, the severity of a patient's diarrhea, and whether the patient is on other medications will all influence the prescribed Imodium AD® dosage.
The main factor that affects Imodium AD® dosage is the age of the patient taking the medication. Adults and children over the age of 13 will generally start with a 4 milligram dose and then supplement this initial treatment with 2 milligrams of the drug at a time. The maximum dose for this group is 8 milligrams in a 24 hour period. Children between the ages of eight and 12 will usually take 2 milligrams of Imodium AD® three times a day, while those between the ages of six and eight years will take this same dosage only twice in a 24 hour period. Children younger than six years are not usually given this medication.
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The reason that the age of the patient is so important when determining the proper dosage of Imodium AD® is that children are sensitive to the active ingredient, loperamide. This drug can slow down the contractions of the digestive system to the point where food and waste are not moving though the system at all. It can also make it harder to tell if a child is dehydrated, which can lead to serious health complications.
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The other main factor when determining the dosage of Imodium AD® is the severity of the patient's diarrhea. Adults and teenagers are usually prescribed an initial dose to take at the onset of the diarrhea and then additional doses to take after each bowel movement until symptoms improve. Though there is a maximum daily dosage for adults and teenagers, not all patients will have severe enough symptoms to warrant the use of 8 milligrams in one day. For some patients, the initial dose may be enough to stop diarrhea, while others may need one or two additional treatments in the first day.
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Other medications a patient is taking may also play a role in determining the correct Imodium AD® dosage. Though there are not many drug interactions with this medication, Imodium AD® is known, however, to interact with gemfibrozil and itraconazole. A patient who is taking one of these drugs may be given a smaller Imodium AD® dosage or asked to take Imodium AD® less frequently.