Corns and calluses are probably the most common problem that Podiatrists treats. Corns on the feet are due to too much pressure. That higher pressure causes the skin to thicken up to protect itself. The skin then becomes so thick that it becomes painful. That pressure could be due to a number of things like hammer toes, bunions or dropped metatarsals. The only way to permanently get rid of a corn is to take away the excessive pressure that is causing it. There is no other way. That means addressing the shoe fitting so that there are no pressure and address the bunions and hammer toes. Cutting a corn out just takes away the hard skin and it does not take away the cause. The corn will come back sooner or later if that cause is still there. That cause needs to be addressed or it will be an ongoing problem long term. Corns do not have roots that they grow back from.
A popular method to try and treat corns is to use medicated corn removal pads. The idea behind the corn removal pads is that they contain an acid that is supposed to eat at the corn to get rid of it. You apply the medicated pad over the corn and leave it in place until it has eaten away at the corn to get rid of it. The problem is that the acid in the corn removal pad does not know what is corn and what is done corn, so its going to eat away at whatever you put it one including the normal skin. That can be dangerous and even more dangerous in those who have underlying conditions such as diabetes. The pad may be able to get rid of some of the corn in the short term and give some pain relief, but that corn is just going to grow back again because that excessive pressure that caused them is still there.