Can Invega Sustenna (paliperidone) cause increased thirst?

Can Invega Sustenna Cause Increased Thirst?

Increased thirst is not a documented or recognized adverse effect of Invega Sustenna (paliperidone palmitate) based on available clinical evidence and prescribing information.

Understanding the Side Effect Profile

The established adverse effects of paliperidone palmitate do not include polydipsia or increased thirst as a common or documented reaction 1, 2. The most frequently reported adverse events in clinical trials include:

• Extrapyramidal symptoms (13-26% depending on dose), including dystonia, tremor, and parkinsonism 1, 3
• Headache (11-18% of patients) 1
• Insomnia (4-14% of patients) 1
• Injection site reactions (unique to the long-acting formulation) 2
• Prolactin-related adverse events (4% in long-term trials) 1, 4

Important Metabolic Considerations

While increased thirst itself is not listed as a side effect, you should evaluate for hyperglycemia and diabetes, which can present with polydipsia 5, 6. Antipsychotics as a class, including paliperidone, require metabolic monitoring because they can cause:

• Weight gain and metabolic syndrome 5
• Elevated fasting glucose and HbA1c 5, 6
• Dyslipidemia 5, 6

Baseline and ongoing monitoring should include: fasting glucose or HbA1c, lipid panel, BMI, waist circumference, and blood pressure at baseline, 3 months, and then annually 5, 6.

Clinical Approach to This Patient

If your patient reports increased thirst on Invega Sustenna:

1. Check fasting glucose and HbA1c immediately to rule out drug-induced hyperglycemia or diabetes 5, 6
2. Assess for other causes of polydipsia including psychogenic polydipsia (common in schizophrenia patients), diabetes insipidus, or other medical conditions
3. Review concurrent medications that may cause dry mouth or thirst
4. Evaluate for hyperprolactinemia, which can occasionally present with various symptoms 1, 4

Key Caveat

The absence of thirst as a documented side effect in the paliperidone literature does not mean it cannot occur in individual patients, but it suggests this is not a direct pharmacologic effect of the medication 1, 2. The symptom warrants investigation for alternative etiologies, particularly metabolic complications that are well-established with antipsychotic use 5, 6.