I Am Concerned About My Husband. He Has Had Moderately

I am concerned about my husband. He has had moderately high blood pressure for over a year now and has been taking medication. At a doctor's appointment about 6 weeks ago, his BP was 190/100, so his doctor increased his dosage. About four weeks ago he caught a cold and it took 2 weeks to pass. Since then he has not been feeling well, describing his primary symptom as light headedness. Should he be seeing his doctor immediately? He is 74 years old and generally in very good health. Thank you, Eva Pomeroy