Brief Answer:
investigation is required

Detailed Answer:
Hello,

You haven't mentioned any symptoms so I gather you're otherwise healthy and symptom-free...

The causes of lower platelets count are many and in most cases they can't be approached that easy. First of all you've got to make sure the automated counter was right. Sometimes the counters get confused and count more cells as white blood cells in the expense of platelets, causing high white blood cells count and low platelets count. The result can be confirmed by repeating the test and with microscopic examination. Microscopic examination may also provide additional information about various blood cells and provide clues to certain diagnoses.

I'll mention some potential causes and my assumption about what might have gone wrong in your case...
- low platelet production: leukemia, lymphoma, bone marrow infiltration by cancer cells, drugs, toxins (including alcohol), certain viruses like the Epstein-Barr virus, etc.
- increased platelet destruction or removal: enlarged spleen, autoimmune conditions, drugs, infections, etc.

A drug that is commonly used when placing a pacemaker is heparin and similar anticoagulants. Heparin may cause increased platelet destruction and low platelet counts after the fifth day from treatment initiation. This is something that your doctor has to consider.

Your first step regarding the platelets issue is to repeat the blood count and also do a microscopic examination of peripheral blood. Then a hematologist should take over to guide the investigation strategy.

Metformin is not supposed to cause low platelets. Having 134 is consider a little higher than the target levels for fasting glucose. A single measurement is not sufficient to guide treatment decisions. Your glucosylated hemoglobin A1c and serial self measurements of blood glucose are important in that regard.

I hope you find my comments helpful!
You can contact me again, if you'd like any clarification or further information.

Kind Regards!

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