Can Prolia (denosumab) cause urine to be bright yellow?

Denosumab (Prolia) Does Not Cause Bright Yellow Urine

Denosumab (Prolia) does not cause bright yellow urine discoloration as a known side effect. Based on comprehensive clinical guidelines and drug information, urine discoloration is not listed among the documented adverse effects of denosumab therapy 1.

Known Side Effects of Denosumab

Denosumab is associated with several well-documented side effects, but urine discoloration is not among them:

Common Side Effects:

• Musculoskeletal symptoms: arthralgia (14.3%), back pain (11.5%), extremity pain (9.9%), muscle pain (6.0%) 1
• Infections: increased risk (risk ratio 1.26), including nasopharyngitis, upper respiratory infections, and urinary tract infections 2, 1
• Skin reactions: rash/eczema (odds ratio 1.96) 2, 1
• Gastrointestinal symptoms: mild upper GI symptoms (odds ratio 1.74), constipation 2, 1
• Headache 1
• Hypocalcemia (especially within first month of treatment) 2, 1

Serious Side Effects:

• Osteonecrosis of the jaw (rare but serious) 2, 1
• Atypical femur fractures 2, 1
• Severe hypocalcemia 1

Medications Known to Cause Urine Discoloration

While denosumab is not associated with urine discoloration, several other medications are known to cause this effect:

1. Metronidazole: Can cause cola-colored or dark urine 3
2. Propofol: Can cause green or pink-cloudy urine discoloration 4
3. Rifampin: Can cause orange discoloration of secretions and urine 2
4. Ethambutol: Not associated with urine discoloration but can cause optic neuritis 2

Possible Causes of Bright Yellow Urine

If a patient taking denosumab experiences bright yellow urine, consider these alternative explanations:

1. Vitamin supplements: High-dose B vitamins (particularly B2/riboflavin) can cause bright yellow urine
2. Dehydration: Concentrated urine appears more yellow
3. Medications: Other medications the patient may be taking concurrently
4. Diet: Foods with strong pigments or food colorings
5. Medical conditions: Liver or biliary conditions can affect urine color

Clinical Approach for Patients with Urine Discoloration

If a patient on denosumab reports bright yellow urine:

1. Review all medications and supplements the patient is taking
2. Assess hydration status
3. Consider recent dietary changes
4. Evaluate for signs of liver dysfunction or biliary issues
5. Perform urinalysis if clinically indicated
6. Reassure the patient that denosumab is not known to cause urine discoloration

Monitoring Recommendations for Denosumab

While urine monitoring is not required for denosumab therapy, patients should be monitored for:

• Calcium levels (risk of hypocalcemia) 2, 1
• Signs of infection 2, 1
• Oral health (risk of osteonecrosis of the jaw) 2, 1
• Bone pain in thighs, hips, or groin (risk of atypical fractures) 2, 1

In conclusion, if a patient on denosumab reports bright yellow urine, the clinician should investigate other causes, as this is not a known side effect of denosumab therapy.