Hello,
Thanks for your query.

I appreciate your efforts for medical consultation in so much distress.

Important aspects of your query are:
•     56 year old male
•     Known case of Bipolar disorder on Lithium 800mg per day
•     Concern related to use of Thiocolchicoside 16mg per day for back pain with lithium

Lithium is a mood stabilizer and used in Bipolar disorder. It serum level should be monitored to prevent toxicity.

Thiocolchicoside is a muscle relaxant with anti-inflammatory and analgesic effects. It is used for muscular pain.

There is no documented direct interaction of thiocolchicoside and lithium. But thiocolchicoside usually come in combination with NSAID like paracetamol, nimesulide or aceclofenac. All NSAIDs are known to increase serum lithium level which can lead to toxicity. So, please check your thiocolchicoside preparation to rule out combination with NSAID. Thiocolchicoside also cause dizziness and confusion in some cases. Frequency of these side effects increased with Lithium due to same side effects with it.

Apart from that I would also advised to check your lithium level currently.

I hope this information has been both informative and helpful for you. In case of any doubt, I will be available for follow ups.

Wish you good health.
Regards,

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Hello again,

Thanks for follow up,

It is good that your serum lithium level is well maintained (0.65) toward the lower side of normal range (0.6-1.2). It will also give you safety in case of Li level increase with paracetamol slightly.

There is no much issue of using thiocolchicoside with lithium. But as paracetamol may increase your lithium level then I would like to advice you to have serum lithium level after 1 week of start of paracetamol daily.

Please accept my answer in case there are no further queries and recommend our services to your friends too if you have found it helpful.

Wish you good health.
Regards.

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