Any one here ever treated your kitty with Lactulose for constipation?

You can not treat a cat for constipation with lactulose - or almost anything given through the mouth. Constipation is a blockage in the intestines and oral treatments won't clear it. However, you can use lactulose as a preventive to minimize future problems if your cat is prone to constipation (usually caused by dehydration). Typically, you have to visit a vet and they can determine the best method to correct it according to where it is located and how bad it is.

I seriously worry about humanity when I see questions like this. Seriously.

"Lactulose is useful in treating people with chronic constipation due to forgetting or ignoring the need for defecation." -- Wikipedia

It sounds like maybe you're not gonna get the gold medal for decision making, eh?

First thing you need to do is go to your doctor and request a permanent form of birth control for yourself first.

"How good is it?" -- NOT AT ALL. Lactulose is a drug made for HUMANS. Which is a DIFFERENT SPECIES than a CAT.

"I got it on my kitties face" - sounds like you got it on her face when you were trying to shove it down her throat -- NOT SMART.

PSA here, people:

Drugs in your cabinet, whether prescription or over the counter are NOT for your pets. They are for HUMANS. Many drugs that are for humans are toxic to cats and/or dogs (and lions and tigers and bears, oh my!). NEVER yank something out of YOUR medicine cabinet and give it to your pet. It is in YOUR medicine cabinet for a reason.

IF and ONLY IF your vet says you can just get XYZ medicine for your cat, you can give your cat that medicine.

NEVER NEVER give your pets stuff that was meant for YOU.

Yeesh.

I would recommend over the counter miralax. 1/8th a teaspoon in the food 2x a day

Stop feeding dry food before other problems start to happen

no i haven't.