Last time I looked into all this a while back, eg on Examine.com—an excellent site which analyses research on supplements—Healthspan Elite Zinc Defence Lozenges seemed to be the only suitable zinc lozenge available in the UK for treating colds once you have them. Doesn’t come with instructions (!) but as soon as cold symptoms start, dissolve slowly in the mouth and avoid eating/drinking for say 15 min afterwards, and avoid citric acid for a while before too. You need to take 9 lozenges (1 sheet) per day.
Examine.com also suggests black elderberry, eg Sambucol Immuno Forte. High doses of vitamin C may also shorten colds slightly, and help prevent them in people who have very high physical activity eg athletes & soldiers. Zinc (swallowed pills, not lozenges) may also help prevent colds.
Evidence for all these things is weak IIRC but fairly harmless to try, particularly if (as for me) your colds are frequent, persistent, or annoying.
Last time I looked into all this a while back, eg on Examine.com—an excellent site which analyses research on supplements—Healthspan Elite Zinc Defence Lozenges seemed to be the only suitable zinc lozenge available in the UK for treating colds once you have them. Doesn’t come with instructions (!) but as soon as cold symptoms start, dissolve slowly in the mouth and avoid eating/drinking for say 15 min afterwards, and avoid citric acid for a while before too. You need to take 9 lozenges (1 sheet) per day.
Examine.com also suggests black elderberry, eg Sambucol Immuno Forte. High doses of vitamin C may also shorten colds slightly, and help prevent them in people who have very high physical activity eg athletes & soldiers. Zinc (swallowed pills, not lozenges) may also help prevent colds.
Evidence for all these things is weak IIRC but fairly harmless to try, particularly if (as for me) your colds are frequent, persistent, or annoying.