Formulation

Lactobacillus reuteri is available in a variety of dosage forms, including capsules, regular tablets or chewable tablets, liquid drops, lozenges, and powders.

There are many different strains of L. reuteri. Each strain has a slightly different genetic makeup, meaning the effect of the probiotic can vary between strains. The most commonly studied strains for infantile colic and gastrointestinal health are DSM 17938 and ATCC 55730.^{[1][2][3][4][5][6]} For oral health, most studies have used strains DSM 17938 and ATCC PTA 5289.^{[7][8][9][10]} Other studied strains include ATCC PTA 6475, RC-14, NCIMB 30242, and DSM 17648.^[11][12]

Of note, L. reuteri ATCC 55730 is not available commercially, but it is considered relatively equivalent to its daughter strain, DSM 17938.^[13]

Range of dosages studied

Dosages of L. reuteri have ranged from 1 x 10⁷ (ten million) colony-forming units (CFUs) to 1 x 10¹¹ (one hundred billion) CFUs per day, for durations of 5 days to 6 months. In children and infants, dosages have usually been limited to 1 x 10⁹ (one billion) CFUs daily.