Nicotine Patches
The benefit of the patch is that it provides a consistent level of nicotine in the bloodstream. No peaks and valleys here. However, there are some drawbacks as well. You can develop skin irritation around the site of the patch. Also, you'll need to be very careful to pick the appropriate amount of nicotine — most patches come in a variety of strengths — because if you go too high, then you could be facing side effects like restlessness, rapid heartbeat, and irritability.
The Gum
The gum is a great option for those who would rather be able to have nicotine exactly when they want it. Though the nicotine absorption here — through your gums — is definitely slower than inhaling smoke, it's still going to hit you faster than the patch. Again, you'll want to carefully assess what strength you need to avoid taking in too much nicotine. Beyond the possibility of shakiness, jumpiness, and irritability, nicotine gums can also have unfortunate digestive side effects.