Method of cleaning drains utilizing halogen-containing oxidizing compound

A method of substantially removing a restriction from a drain pipe system comprising the steps of:

• introducing to a drain pipe system having an organic restriction a dry cleaning composition comprising a gas generation/entrapment carrier and a non-caustic drain opening active comprising at least one halogen-containing oxidizing compound in an amount from about 10% to about 90% by weight of cleaning composition;
• activating the cleaning composition by adding a sufficient amount of water to the drain pipe system while maintaining a flow-through state in the pipe system;
• allowing the drain opening active to remain in contact with the restriction for a sufficient time to substantially degrade the restriction;
• and
• rinsing the drain opening active and restriction from the pipe system, wherein the restriction removing method improves the water flow rate of the pipe system by an average of at least 0.7 liters/min. after 16 hours of the drain opening active contacting the restriction.