I have a 43 watt 120 volt light bulb that burnt out?

It depends on the socket and where it is. Some sockets can't handle a higher wattage, and if it is in some sort of enclosure the heat might be too much with a higher watt bulb. You can only use 110-120 volt bulbs with 110-120 volt supply. CFL lamps draw about 1/4 the current of an equivalent incandescent. For instance a 26 watt CFL puts out as much light as a 100 watt incandescent.

I never heard of either 43 or 72 watt light bulbs. Where did you get these odd things? Standard sizes are 40, 60, 75, or 100 watts if you are using incandescents.