Linzess contains linaclotide as its active ingredient. The inactive ingredients vary depending on the dosage strength of the capsules:
For 145 mcg and 290 mcg capsules, the inactive ingredients include calcium chloride dihydrate, hypromellose, L-leucine, and microcrystalline cellulose. Gelatin and titanium dioxide are used to make the capsule shell.
For 72 mcg capsules, the inactive ingredients consist of calcium chloride dihydrate, L-histidine, microcrystalline cellulose, polyvinyl alcohol, and talc. The capsule shell is also composed of gelatin and titanium dioxide.