The specific reasons for the ban of Zudena 100 mg tablets can vary by region, but common reasons for a medication's ban include:

1. Regulatory Issues: The drug may not have met the regulatory requirements for approval or continued use in certain countries. This could be due to concerns about its safety, efficacy, or manufacturing practices.
2. Safety Concerns: There might be reports of adverse effects or serious health risks associated with the medication that led to regulatory authorities deciding to withdraw it from the market.
3. Quality Control Problems: Issues related to the quality of the medication, such as contamination or inconsistent potency, could lead to a ban.
4. Patent or Legal Issues: Sometimes, medications are banned due to legal disputes, such as patent infringements or intellectual property conflicts.
5. Market Withdrawal: The manufacturer may voluntarily withdraw the drug from the market for various reasons, including business considerations or strategic changes.

If you’re concerned about the status of Zudena or any other medication, it’s a good idea to consult with a healthcare professional or check with regulatory authorities for the most accurate and current information.