The rise of the popularity of saline nasal douches, with several commercial preparations available, may be a rediscovery of an age-old tradition, but it has been shown to benefit patients. The question then arises as to whether this can be improved by adding in various medications, especially in recalcitrant cases of chronic rhinosinusitis (CRS) in patients who perhaps have had several operations. This paper pulls together information on anti-infective additives (rather than corticosteroid or anti-inflammatory additives), which include topical antibiotics (e.g. mupirocin, gentamicin, tobramycin), topical antifungals and ‘additives’ which include surfactants, xylitol, manuka honey and N-Chlorotaurine (an antiseptic). The overall message is that such additives are not part of the routine management of standard CRS patients, but should be reserved for recalcitrant cases, but that research is weak on most of these categories (apart from antibiotics). The evidence on antifungals is particularly weak and these are not recommended. Clearly, there is a long way to go before we have enough evidence to recommend use of these categories of additives to douches with a good evidence base, except for antibiotics and, even in those cases, there are many unanswered questions (dose, risk-benefit balance, outcomes, case selection, etc).