At Cadabams Hospitals — a 33-year psychiatric institution with hospitals in JP Nagar (Bengaluru), Whitefield (Bengaluru), and Cadabams Spark Hospital Mysore — a recurring clinical scenario is the patient who tried a medication, found that it didn't work or produced significant side effects, and assumed they were "failing treatment". Often what happened was much more biological: their body metabolises that medication differently from the average patient.
Why does the same psychiatric medication work differently for different people? The answer involves drug metabolism, body composition, age, and a relatively new clinical tool — pharmacogenomic testing. Dr. Kishan Anwar, Consultant Psychiatrist at Cadabams, explains. 24/7 helpline: 97414 76476.
Rapid Versus Slow Metabolisers
The key variable in individual medication response is how quickly the body processes and eliminates the medication. In rapid metabolisers, the drug is cleared from the system faster — therapeutic blood levels drop more quickly, and the patient may need higher doses or more frequent dosing to maintain effect. In slow metabolisers, the medication accumulates and produces stronger effects (and stronger side effects) at standard doses.
Same medication. Same dose. Different bodies. Different outcomes.
Pharmacogenomic Testing in India
Can the response to a psychiatric medication be predicted before it is prescribed? The answer is increasingly yes. Pharmacogenomic studies — genetic testing that examines how a patient's specific genetic profile affects the way they metabolise and respond to particular medications — are available in India.
These tests examine the relevant genes involved in drug metabolism and provide guidance on which medications a patient is likely to metabolise quickly, slowly, or unusually. While not yet standard practice across all presentations, they are available and can be clinically useful — particularly for patients with a history of unusual reactions, treatment resistance, or significant side effects across multiple trials.
What the Clinical Team Does When a Patient Is Sensitive to Medication
The response depends on the combination of side effects and therapeutic benefit. If there are significant side effects with very little clinical response, the options are switching to a different medication or augmenting with a second one. If side effects are significant but the medication is working, dose reduction or a different formulation may resolve the issue while preserving the benefit.
At Cadabams, the clinical team also factors in age (elderly patients are often slow metabolisers), body composition, hepatic and renal function, and concurrent medications (drug interactions can mimic genetic metabolic differences).
Related reading from Cadabam's Hospitals: psychiatric medication, how long medication takes, and emotional blunting.