Being one that was not good at holding doses when we were new because Gracie was young and I wanted her in lower numbers
and I didn't fully understand how the insulin works, I think if the nadirs are where you want them but he's bouncing, it's worthwhile to give him more time on a dose and see if the cumulative nature of lantus starts to trend the overall curve down a bit. Some cats are very slow responders. But if you see the nadirs trending up, it's time to increase the dose.
I've also done the method Jen is discussing. It really takes some commitment because you are basically overdosing the cat a bit and then keeping the numbers from dropping lower by feeding a
higher low carb food....that's the goal, at least. You don't want to increase the dose so much that you have to prop up with HC all the time. Generally, you want to anticipate where they go lowest in the cycle and feed a
higher low carb food before they get there; also feeding him extra of the higher low carb at that time can help. Occasionally, we have to throw in the higher carbs but you don't want to be propping up the numbers every single cycle with HC. So try a 10% food and a little extra of it.
On Chris's comment: the only time we would suggest a new member feed at shot time is if you test and get a 40 something number. The guidelines say if you get a 40 something at PS to not feed at the first 40s number but wait 15 mins, retest and if he's not coming up, give him a small amount of LC and retest a little later. The theory being that the LC is going to raise the BG enough to shoot but so much that you would be shooting a food spike. One thing I do recommend to members is if the kitty is breaking a bounce and headed downhill so that by +10, you've got a lower number (e.g. 60s or so) and
you know your cat's patterns well enough to know he's going to keep dropping, it's ok to feed some LC right before that +10.
Once you really know him and you feel comfortable with knowing what kind of food spikes he gets when, etc, then I don't think it's a big deal to feed a little LC between +10 and when you shoot
if he is really coming down as long as the amount you feed is a very little LC. You want to know his patterns well enough to know he doesn't get much, if any food spike from a small amount of LC so you are shooting a realistic number. But if you don't understand that about your cat, it's best to not do it. "Why not" you ask? Well, if you don't know how much he spikes, consistently, and he comes up quite a bit from a little LC, you shoot, he onsets, and then he drops like a rocket and you are up all night.
The other thing that is very important is what he's doing coming into the +10 through PS timeframe. If he's flat as a board, I would not feed unless he's below 50 and then I'd follow the "Dealing with Low Preshots" post. If he's a flat 60, for instance, I'd shoot it, no food. Don't get in the habit of feeding a perfectly good, flat, surfing number because, with lantus, he's probably going to come up after you shoot and feed.