Good. If he already has an insulin Rx, then he just needs to fine tune his dosage and timing, which doesn't cost a thing. The information is on the web, as well as with nurse counselors. He can probably get a free consultation with the pharmacist who dispensed his insulin, too. First thing I'd do is try to find him a diabetes support group locally. They're free, or nominal cost.
The big spikes in blood sugar are what he needs to avoid. The capillary damage occurs with blood sugar levels >250. To prevent those, he may need to lower his carb serving sizes at meals, eat smaller meals more frequently, and inject insulin after every meal, instead of once or twice/day. It sounds like he leads a hectic, stressful life. He needs to drop into a scheduled eating/medication cycle where he's in control of the disease, not v.v.
Here's a
primer on adjusting insulin dosage.
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