Can I take Hydroxocobalamin and Mirtazapine together?

Why this happens

Hydroxocobalamin (a form of Vitamin B12) and mirtazapine (an antidepressant) are processed by the body through different pathways. Hydroxocobalamin is a water-soluble vitamin that does not interfere with the liver enzymes responsible for breaking down mirtazapine. Furthermore, they do not have overlapping side effects that would cause concern.

What you should do

You can continue to take both medications as prescribed by your doctor. No special precautions or monitoring are required beyond your usual routine. If you experience any new or unusual symptoms, you should still consult your healthcare provider.

Important precautions

Suicidal thoughts and behaviour

Mirtazapine can cause an increase in suicidal thoughts or self-harm, particularly when first starting treatment or changing the dose. Patients and carers should monitor for changes in mood or behaviour and seek urgent medical help if these occur.

Agranulocytosis (low white blood cell count)

Mirtazapine can cause a dangerous drop in white blood cells. You must contact your doctor immediately if you develop signs of infection, such as a high temperature, sore throat, or mouth ulcers.

Hypokalaemia (low potassium)

When starting treatment for severe vitamin B12 deficiency, your potassium levels can drop rapidly as your body produces new red blood cells. This can be dangerous for your heart and may require monitoring by your doctor.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol while taking mirtazapine. Both alcohol and mirtazapine cause drowsiness and can affect your coordination; combining them significantly increases these sedative effects, making you feel very sleepy and increasing the risk of accidents.

It is best to avoid or strictly limit alcohol while receiving hydroxocobalamin treatment. Excessive alcohol consumption can interfere with the absorption of Vitamin B12 and may worsen the underlying deficiency being treated. Combining alcohol with medication also increases the risk of liver strain.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.