Drug regulator orders fresh safety labels for five common antimicrobials

New Delhi: India's drug regulator has ordered immediate safety label updates for five widely used antimicrobial medicines after fresh data identified previously unlisted adverse drug reactions.

The Central Drugs Standard Control Organization (CDSCO) directed state licensing authorities on 6 July to ensure that manufacturers revise the prescribing information leaflets and promotional literature for tetracycline (used for bacterial infections like acne and respiratory tract issues), vancomycin (indicated for severe bacterial infections), metronidazole (used for bacterial and parasitic infections), cotrimoxazole (a combination antibiotic used for urinary and chest infections), according to official documents reviewed by Mint and two people familiar with the matter.

The move follows a review of adverse-event reports, which include unintended or harmful responses, to a medicinal product, submitted under the Pharmacovigilance Programme of India (PvPI). The safety assessments were endorsed by the relevant subject expert committees (SEC).

The updated warnings are intended to alert doctors and patients to rare but potentially serious reactions, ranging from localized rashes to severe hypersensitivity reactions, that surfaced after the medicines entered widespread clinical use.

“Drug quality and patient safety do not end when a medicine receives regulatory approval," said Dr Aijaz Ilmi, senior consultant & head of preventive wellness & metabolic diseases, Pacific OneHealth. “Once a medicine is used by large and diverse populations in real-world settings, rare, delayed or population-specific adverse reactions may emerge that are not always evident during clinical trials. This is why pharmacovigilance is a critical pillar of modern healthcare.”

While most adverse drug reactions are mild and manageable, some can be serious if not detected and reported promptly, Ilmi said. "Strengthening pharmacovigilance ultimately improves patient trust, treatment outcomes and public health protection,” he added.

Queries sent to the health ministry and DCGI office weren't answered immediately.

Labelling drugs

Under the revised safety guidance, manufacturers of tetracycline, metronidazole and cotrimoxazole must add fixed drug eruption (FDE) to the list of adverse drug reactions in the prescribing information.

Vancomycin must now carry a warning on DRESS syndrome—a rare but potentially life-threatening hypersensitivity reaction marked by widespread rash, fever and internal organ damage. Manufacturers of oral itraconazole have been directed to include symmetrical drug-related intertriginous and flexural exanthema, a distinctive rash affecting skin folds such as the groin and armpits.

Drugs Controller General of India (DCGI) Dr Rajeev Singh Raghuvanshi, has asked state regulators to roll out the labelling orders immediately and report the action taken to ensure manufacturers comply with the revised requirements.

The regulator said the National Coordination Centre for the Pharmacovigilance Programme of India (NCC-PvPI) evaluated adverse drug reaction data based on individual case safety reports, following which the relevant expert committees recommended updating the safety information for the affected medicines.

For antibacterial and antiparasitic medicines, the SEC recommended that CDSCO direct state drug controllers to ensure the newly identified adverse reactions are incorporated into the corresponding prescribing information leaflets. The SEC on dermatology and allergy made a similar recommendation for flexural exanthema.

According to Crisil Market Intelligence and Analytics, the market size of the anti-infective segment in India, which includes antibiotics, antivirals, and antifungals, stood at about ₹251.3 billion for FY2024.