Precautions

Drug information provided by: IBM Micromedex

It is very important that your doctor check your progress at regular visits, to allow changes in your dose and help reduce any side effects. Blood tests may be needed to check for unwanted effects.

Do not take mirtazapine with a monoamine oxidase (MAO) inhibitor (eg, isocarboxazid [Marplan®], linezolid [Zyvox®], methylene blue injection, phenelzine [Nardil®], selegiline [Eldepryl®], tranylcypromine [Parnate®]). Do not start taking mirtazapine during the 2 weeks after you stop a MAO inhibitor and wait 2 weeks after stopping mirtazapine before you start taking a MAO inhibitor. If you take them together or do not wait 2 weeks, you may develop confusion, agitation, restlessness, stomach or intestinal symptoms, a sudden high body temperature, an extremely high blood pressure, or severe seizures.

Mirtazapine may cause a serious condition called serotonin syndrome if taken together with some medicines. Do not use mirtazapine with buspirone (Buspar®), fentanyl (Abstral®, Duragesic®), lithium (Eskalith®, Lithobid®), tryptophan, St. John's wort, or some pain or migraine medicines (eg, rizatriptan, sumatriptan, tramadol, Frova®, Imitrex®, Maxalt®, Relpax®, Ultram®, Zomig®). Check with your doctor first before taking any other medicines with mirtazapine. Check with your doctor right away if you are having agitation, difficulty in breathing, a fast heartbeat, hallucinations, a high fever, high or low blood pressure, increased sweating, loss of bladder control, seizures, severe muscle stiffness, unusually pale skin, or tiredness while you are taking this medicine.

Mirtazapine may cause some teenagers and young adults to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. Some people may have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. If you or your caregiver notice any of these unwanted effects, tell your doctor right away. Let the doctor know if you or anyone in your family has bipolar disorder (manic-depressive) or has tried to commit suicide..

This medicine may add to the effects of alcohol and other CNS depressants (medicines that make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicines, prescription pain medicine or narcotics, medicine for seizures or barbiturates, muscle relaxants, or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are taking this medicine.

This medicine can temporarily lower the number of white blood cells in your blood, increasing your chance of getting an infection. If you can, avoid people with infections. Check with your doctor right away if you think you are getting an infection or if you have a fever or chills, sore throat, sores in the mouth, lower back or side pain, or painful or difficult urination.

Do not suddenly stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are using before stopping completely. This may help prevent a possible worsening of your condition and reduce the possibility of withdrawal symptoms such as headache, nausea, or a general feeling of discomfort or illness.

This medicine may increase your weight. Your doctor may need to check your weight on a regular basis while you are using this medicine.

Mirtazapine may cause drowsiness, trouble with thinking, or trouble with controlling body movements. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that requires you to be alert, well-coordinated, and able to think well.

This medicine may cause serious skin reaction, including drug reaction with eosinophilia and systemic symptoms (DRESS). Check with your doctor right away if you have black, tarry stools, chest pain, chills, cough, fever, painful or difficult urination, sore throat, sores, ulcers, or white spots on the lips or in the mouth. swollen glands, unusual bleeding or bruising, or unusual tiredness or weakness.

Hyponatremia (low sodium in the blood) may occur with this medicine. This is more common in elderly patients, those who are taking diuretic medicines for high blood pressure, or those who have decreased amounts of fluid in the body due to severe diarrhea or vomiting. Check with your doctor right away if you have confusion, difficulty concentrating, headaches, memory problems, weakness, and unsteadiness.

Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

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