It is a very lucrative idea to buy Levoxyl online, but one must be sure of the dosage of the medication. While the 100 mcg pill works for most people, acute cases may demand the 200 mcg pill. Never make them mistake of taking two pills together, in case you miss a dosage of Levoxyl. In most cases the pill is a lifetime medication and since it helps produce the natural hormone, it is a fairly safe medication. But Levoxyl does interfere with the absorption of other medicines like antacids, calcium carbonate, iron pills, Bile Acid Sequestrants and other similar medications.