We taper off these drugs slowly in order to keep withdrawal symptoms to a minimum. That way we can function-- go to work, drive the car safely, and not alienate everybody in the household.
Tapering off slowly, however, keeps you exposed to this neurotoxin for a longer period of time, and there is a greater risk of encountering medication toxicity. Even though the drug is being gradually reduced, your organs are still being exposed; therefore, it's important to monitor your symptoms throughout the weaning program.
Cross-tapering (uploading a second drug while reducing the first one) can exacerbate medication toxicity if the second drug is of a similar type, like another serotonin-related med. Physicians would normally be aware of negative drug interactions, but you can check it yourself by going to www.drugs.com and see Interactions.
Should symptoms of toxicity emerge, it's time to consider quitting immediately-- Cold Turkey! Areas of concern would include (but are not limited to) the following: liver, kidney, signs of tariff dyskinesia, skin rash, Serotonin Syndrome, heart arrhythmia, suicide planning, self-harm, and mania. Of course it's recommended that you have your physician in the loop while you are withdrawing.