- Malabsorption and gut dysbiosis
- Increased oxidative stress and mitochondrial dysfunction
- Higher metabolic needs for methylation and energy production
Children with Down syndrome are particularly vulnerable. When you add Lasix to an already thiamine-depleted child, you risk triggering a biochemical cascade that can manifest in serious and even life-threatening symptoms.
- Fatigue, lethargy
- Poor feeding, vomiting
- Constipation, gastroparesis, and reflux
- Muscle weakness, hypotonia
- Developmental delays and irritability
- Tachypnea or labored breathing
- Cardiomegaly, heart failure symptoms
- Recurrent vomiting
- Aphonia (loss of voice)
- Edema and heart failure
- Lactic acidosis
- Esotropia (crossed eyes)
- Gastrointestinal dysmotility
- Sudden cardiovascular collapse
Thiamine deficiency can lead to vasoconstriction and increased vascular resistance, possibly through disruption of mitochondrial energy metabolism in the pulmonary vasculature.
This means that giving Lasix to a child with Down syndrome and pulmonary hypertension, without concurrent thiamine repletion, can worsen the condition it was intended to treat.
When supplementing a child on Lasix to prevent or correct thiamine and magnesium deficiency, age-appropriate dosing is key. Benfotiamine, a fat-soluble derivative of thiamine with superior cellular absorption, is generally well tolerated and effective. For children ages 1 to 3 years, a typical starting dose is 25-50 mg once daily. For ages 4 to 8, consider 50-100 mg daily, and for older children 9 and up, 100-150 mg per day is often appropriate. Some clinicians may use higher doses in acute deficiency or if symptoms of beriberi or pulmonary hypertension are present. |
Magnesium glycinate is commonly used to replenish magnesium lost through diuretics. A general guideline is 5-10 mg of elemental magnesium per kg of body weight per day, divided into 1-2 doses. For example, a 20 kg child might receive 100-200 mg of elemental magnesium daily. Always adjust dosing based on individual needs, lab markers, and clinical symptoms, and consult with a pediatric provider knowledgeable in nutritional medicine. |
- Supplement thiamine daily in children on Lasix or other diuretics
- Ensure adequate magnesium status via bloodwork (preferably RBC magnesium)
- Monitor for signs of fatigue, vomiting/reflux, constipation, or neurodevelopmental delay
- Re-evaluate the need for continued diuretic therapy as the child's condition stabilizes
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