Lithium/Selected Phenothiazines Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When lithium and phenothiazines are given together they may produce increased effects that may not be seen when either medicine is given alone.

What might happen:

You may experience symptoms of confusion, delirium, seizures, palpitations, a slow heart beat, or sleepwalking.

What you should do about this interaction:

Make sure your healthcare professionals (e.g. doctor or pharmacist) know which medicines you are currently taking. Contact your doctor if you notice any symptoms of confusion, delirium, seizures, palpitations, dizziness, lightheadedness, or sleepwalking. The dose of either medicine may need to be changed or one of the medicines may be discontinued.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

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