Plant health is constantly challenged by a wide range of fungal infections, especially during the rainy season when excess humidity creates the perfect breeding ground. [1] These infections not only ruin the beauty and vitality of ornamental plants but can also lead to significant losses in crops. [2] Among the common culprits are fungi such as Aspergillus, Alternaria, Fusarium, and powdery mildew, all of which are notorious for damaging leaves, stems, and roots. [3]

Traditionally, these problems are managed using chemical antifungal sprays, including copper-based mixtures, carbendazim, mancozeb, and triazoles. [4] While effective, these treatments are not without drawbacks, such as fungal resistance, environmental toxicity, and rising costs have become real concerns for farmers and home gardeners alike. [5] This has created a need for newer, safer, and more innovative solutions.

One surprising possibility is the repurposing of medicines originally made for humans. Cotrimoxazole (a combination of trimethoprim and sulfamethoxazole) is a well-known antibacterial drug that works by blocking folate metabolism in microbes. [6] Although it is rarely considered for fungal infections, some recent scientific explorations suggest that drug repurposing can open unexpected doors. [7] Alongside this, beclomethasone, a corticosteroid commonly used in dermatology for its anti-inflammatory effects, may have a role in reducing stress reactions in plants exposed to infection.

When used together, these two medicines could act in more than one way: cotrimoxazole may disrupt microbial communities that help fungi thrive, while beclomethasone might protect plant tissues from further damage. Although unconventional, such a combination raises interesting questions about whether human medicines might have unexplored benefits in plant health.

In this context, the following case series documents three instances that are bamboo, money plant, and hibiscus, where fungal infections were managed with cotrimoxazole and beclomethasone lotion, with promising outcomes.

The first case concerned an indoor bamboo plant with 5 stems kept near the window. During the monsoon season, persistent rains led to heavy black fungal growth along one of the five stems of the bamboo plant. The affected region became soft and discoloured, with fragile tissues that threatened the stem's structural stability.

A mixture of cotrimoxazole and beclomethasone lotion was applied directly to the infected portion every day for a period of two weeks.

This case demonstrated a significant success: while the infected region could not be salvaged, the intervention preserved plant life and enabled regrowth. Without treatment, a complete loss of the bamboo plant was likely.

The second case involved a common indoor money plant grown in a hydroponic setup. The plant developed a fine white powdery coating across stems and leaf undersides. Leaves began yellowing and drooping, suggesting progressive fungal invasion.

The cotrimoxazole and beclomethasone lotion mixture was diluted in water and lightly applied to affected regions twice weekly for three weeks.

This case was notable for the complete recovery of the money plant, which transitioned from near-death to healthy, vibrant growth after treatment.

The final case involved a hibiscus plant that had been a long-time source of bright red blossoms. With the onset of rains, it developed dark circular fungal spots across multiple leaves. The leaves curled, dried prematurely, and fell, while flower production decreased dramatically.

A diluted solution of cotrimoxazole with beclomethasone was sprayed evenly across infected leaves and stems once a week.

This case was especially encouraging because it not only controlled fungal spread but also restored functional vitality the plant’s ability to flower once again.

Despite belonging to different species (bamboo, money plant, hibiscus), all responded positively to cotrimoxazole-based treatment. This hints at a mechanism beyond species-specific effects. Cotrimoxazole action is traditionally antibacterial, it interferes with folate pathways that some fungi also depend upon. Another hypothesis is that it eliminated bacterial co-pathogens that may have promoted fungal colonisation. Beclomethasone, although not antifungal, may have reduced inflammatory-like plant stress responses (such as oxidative injury), preserving surrounding tissues and allowing recovery. Together, may have provided microbial suppression plus tissue protection.

In bamboo (late treatment), the infection destroyed part of the plant but spared the rest. In the money plant (early treatment), recovery was near complete. In hibiscus (intermediate timing), recovery was good, with restoration of function. This highlights that early recognition and timely intervention remain crucial in plant fungal infections, as in human medicine.

Standard antifungal sprays are designed specifically for such conditions, yet here a human medicine offered comparable benefit. The accessibility of cotrimoxazole in household medicine kits may explain why it was tried, underscoring the role of curiosity and improvisation in plant care.

These cases are uncontrolled observations, lacking microbiological confirmation of fungal species. Long-term effects of cotrimoxazole or beclomethasone on plant physiology are unknown.  Not all plant fungi may respond; these results cannot yet be generalised to agriculture or large-scale horticulture.

This case series highlights three real-world experiences where cotrimoxazole combined with beclomethasone lotion unexpectedly helped control fungal infections in bamboo, money plant, and hibiscus. While unconventional and anecdotal, these outcomes open the door to new possibilities in plant pharmacology and experimental horticulture. Plants, much like humans, sometimes respond to unexpected therapies, and the repurposing of medicines across species deserves further attention.

Until larger studies provide evidence, such use remains experimental, but the experiences described here serve as a fascinating reminder of how innovation often begins at the margins of established practice.

I acknowledge all authors for their valuable contributions to this research.