Take a short fast on citrus juices, vegetable juices, and herb teas. Drink lots of water and juices. As soon as you are able, begin eating nourishing food, especially vegetables, fruits, nuts, and beans. Drink fresh carrot juice every day. Eliminate meat, dairy products, white flour foods, and sugar.
Decongestants also increase blood pressure.
Helpful herbs to reduce sinus congestion would include comfrey, slippery elm, fenugreek, mullein, aloe vera, yerba santa, red clover, and white oak bark. Garlic contains a chemical which makes mucous less sticky. Horseradish has it also. Cayenne acts in a somewhat similar manner. Peppermint tea also helps open up the sinus passageways.