Swapping to effect increasing allele in case/control studies

I want to find the effect-increasing allele for a given set of SNPs. For quantitive traits, I understand the effect sign is changed when the A1 and A2 are swapped. How does this work for odds ratios?

 SNP A1 A2 OR 
 rsx A  G  0.99

would the positive effect be 1/OR if I swap the A1 and A2 alleles?