I've Been Taking Clindamycin Hcl (150 Mg Qid) Prophylactically For

I've been taking clindamycin hcl (150 mg qid) prophylactically for 6 days following dental implant surgery (one more day to go), and have developed heartburn as a result. Is it okay to take an antacid (e.g., TUMS) for it? I've been on Nexium qAM for GERD for years, and still take it, but it hasn't prevented the heartburn. Thanks. David