Question about blood sugar numbers

I have a question about blood sugar numbers. My husband was recently diagnosed type 2 and so far the lowest his numbers had been was around the 130’s. This morning fasting was 147 so we added glipizide (sp) for the first time. 40 minutes later it was 73 and I know that’s within normal range but he was shaking, dizzy…etc. My question is do we need to treat this as hypo even though within normal range? We did this time…he had 1/2 a glass of orange juice and shaking stopped. I am also wondering if his numbers for hypo may be different than others since his blood sugar was extremely high for so long and we didn’t know it?