Periodontal abscess is an acute condition requiring an emergency care. Thorough scaling/root planing (SRP) in severely inflamed tissue usually results in marked gingival recession, thus unaesthetic outcome. Objective: To compare clinical outcomes following SRP alone to antibiotics prior to SRP in management of periodontal abscess. Methods: Twenty patients (mean aged 46.2 years) with periodontal abscesses were randomly assigned to one of 4 groups, i.e., (1) SRP alone, (2) systemic doxycycline, (3) local delivery 5% minocycline gel (Periocline®), or (4) local delivery 25% metronidazole gel (Elyzol®). At baseline, drainage of the abscess was performed for all patients. Then, group 1 received SRP, while other groups received antibiotics, according to their regimens starting from day 0. At week 2 where inflammation subsided, SRP was performed for groups 2, 3 and 4. Clinical parameters including gingival recession (REC), probing pocket depth (PPD), clinical attachment level (CAL), plaque index, and tooth mobility were measured at baseline, 1, 2 and 3 months. Results: At baseline, average PPDs ranged 7.5-8.9 mm with average CALs of 7.0-9.4 mm. There were no statistically significant differences in baseline PPDs and CALs among groups. At month 3, all groups demonstrated significant PPD reductions and CAL gains with significantly more REC (p<0.05). Groups 1, 2, 3 and 4 demonstrated changes in REC of 1.3, 1.5, 1.5 and 1.5 mm, respectively. PPD reductions at 3 months were 3.8, 4.6, 4.6 and 5.2 mm, with CAL gains of 2.5, 3.1, 3.0 and 3.7 mm in groups 1, 2, 3 and 4, respectively. However, there were no statistically significant differences in changes in REC, PPD reductions and CAL gains among groups. Conclusion: The use of antibiotics prior to SRP did not result in additional improvements in clinical outcomes when compared to SRP alone in management of periodontal abscess.