THE INVENTION RELATES TO A SOLID PHARMACEUTICAL COM POSITION COMPRISING TELITHROMYCIN OR AN ADDITION SALT THEREOF WITH A PHARMACEUTICALLY ACCEPTABLE ACID, AS AN ACTIVE INGREDIENT, CHARACTERIZED IN THAT IT COMPRISES, RELATIVE TO THE TOTAL WEIGHT OF THE COMPOSITION: - TELITHROMYCIN, OR AN ADDITION SALT THEREOF WITH A PHARMACEUTICALLY ACCEPTABLE ACID, IN A PROPORTION OF TELITHROMYCIN OF BETWEEN 0.1 AND 80% BY WEIGHT, AND - AT LEAST ONE DILUENT HAVING A PLASTIC BEHAVI- OUR, IN A PROPORTION OF TO 50% BY WEIGHT. IT ADVANTAGEOUSLY PROVIDES A TELITHROMYCIN TABLET HAVING A SUBSTANTIALLY REDUCED SIZE, BUT NEVERTHELESS HAVING AN EQUAL DOSAGE OF TELITHROMYCIN, AND HAVING IMPROVED MECHANICAL PROPERTIES.