How long is it supposed to it take for severe damage to be done with macular degeneration?

Usually years. Depends if it is the dry type or wet type - wet type is more aggressive and patients can have submacular hemorrhage with sudden loss of vision; but usually amd takes many years to affect the vision; also depends on if the retinal atrophy is outside of the fovea (center of macula), so vision can be quite good for long time.
Varies. Macular degeneration is variable from case to case. Prediction of the course of the damage is not easily done and is likely to be wrong. Just make sure you are seeing a retinal specialist in ophthalmology who can monitor this and give you treatment when needed.

Related Questions

How long does it take for permanent damage to be done with macular degeneration?

Varies. Each individual patient can progress at different rates. See your retina specialist. The appropriate use of areds vitamins can lessen your risk. Also, stop smoking if you smoke since that worsens the disease. Read more...
Varies. Dry macular degeneration can take months to years to cause permanent damage while wet macular degeneration can reach the point of irreversible damage in days to weeks. This is what makes the wet form so much more threatening to the vision. Read more...

How long does it take for severe damage to last if you have macular degeneration?

Very variable. Macular degeneration can come rapidly within days or it can take years to affect vision. There is a dry macular degeneration that takes years to affect vision but is more common. The more infrequent condition is wet macular degeneration that cause vision damage literally overnight and needs immediate attention. Read more...
Any time. Macular degeneration is a "spectrum" disease: it can be very mild for a very long time, or can become severe rather quickly. Once damage sets in, it tends to progress. The "dry" form is slower to progress but has no good treatments available. The "wet" form is more devastating but there are some good therapies that can control it if caught early. Read more...