Loctite is a liquid sealant that is placed onto the screw's threads prior to insertion into the screw hole. The liquid then forms a seal between the threads and the hole to lock the bolt tightly in place. Three versions of Loctite are available, all with differing levels of bond; green gives the strongest bond, red is in the middle and blue gives the least bond. Loctite is available at most hardware and home improvement stores and usually only requires one or two drops per screw to work.
Try to remove the screw with a standard screwdriver. If the screw is older or using the lowest grade blue Loctite, this may be enough to loosen and remove it. Use a screwdriver head that perfectly fits the screw to avoid stripping it.
Place the point of the screwdriver into the screw head, and tap it lightly three to five times with a light-duty hammer. The impact sometimes is enough to loosen the screw enough to break the Loctite bond. Hit the top of the screwdriver perfectly so as not to damage the screw head.
Heat the head of the screw with a propane torch. Be careful to heat only the screw and not the material around it too much as this can damage the surrounding surface. For the red and green Loctite forms, heat is usually the only way to loosen the bond enough to remove the screw. Remove the screw immediately after heating because the cooling will cause the Loctite to solidify again.
Use a drill with a metal drilling bit to drill out the screw in cases where it is impossible to break the Loctite bond in any other way. This is really the last resort for removing Loctite screws and will destroy the screw.
Be patient when trying to remove the screw that you don't damage it or strip the head.
Use proper torch precautions when heating the screw that you don't injure yourself or create a fire hazard.