I've read that smoking can make luvox (fluvoxamine) less effective and require a higher dosage. is the same true for nicotine gum?

No: it is not the nicotine in tobacco smoke, but some of the ""tars" that seems to cause enzymes in the liver to be increased in activity, so that some drugs are metabolized more quickly in smokers than in non-smokers. Occasionally, I have seen problems when people stopped smoking and their drug levels rose, or when they resumed smoking and drug levels fell.

Sometimes: Nicotine leads to activation of some receptors in the brain which cause excitement in some people. Luvox (fluvoxamine) is a medication that increases serotonin which leads to relaxation or sedation in most people. Any form of nicotine could reduce the sedating effects of Luvox (fluvoxamine) or other serotonin increasing medications.