Hi and welcome to the forum
I can't see any scales sticking up. Which scales are sticking out from the body?
What does the fish's poop look like?
Did the fish bloat up (get fat) overnight?
What symptoms does the fish have besides darker colour, raised scales and not eating?
-------------------
Darker colouration is common on sick fish.
The fish in the pictures is a male. Female dwarf gouramis (Colisa lalius) are silver all over. If the fish are blue or red, or red & blue, they are males.
The fish is covered in excess mucous, which is caused by something in the water irritating the fish, most likely the chemicals.
There's no cure for swim bladder problems and true swim bladder problems are uncommon. If a fish starts floating when it stops swimming, stop feeding dry food for a week and feed frozen and or live food instead. If the problem is resolved by removing dry food the diet, then the issue was air in the intestine. If it isn't fixed by removing dry food, then it's a swim bladder issue.
If a fish sinks to the bottom after it stops swimming that is normally a swim bladder problem but can also be caused by fish eating gravel. Gouramis don't normally eat gravel but some goldfish do.
-------------------
Antibiotics should only be used as a last resort on known bacterial infections that haven't responded to normal treatments. There are gram positive and gram negative bacteria and you need to use the correct antibiotics for the infection. Improper use and mis-use of antibiotics has lead to drug resistant bacteria that kill birds, fish, reptiles, animals and people.
If you use antibiotics, they should be used in a bare tank so the medication can work on the fish and not get wasted on bacteria in the gravel and filter. The hospital tank should be flushed out and refilled with clean dechlorinated water before more antibiotics are added.
-------------------
Dwarf gouramis (Colisa lalius) and all their colour forms are regularly infected with the Gourami Iridovirus and or Fish Tuberculosis (TB). There's no cure for either. I doubt this is the Gourami Iridovirus so that's a plus. However, if the fish bloated up overnight, stopped eating and did a stringy white poop, then it has internal organ failure and is dying. This can be caused by Fish TB or by medications, old age and or stress.
If the fish did bloat up overnight, stop eating and do a stringy white poop, it should be euthanised. Once organs have been damaged the fish is going to die and no medications will save them.