Ir al contenido principal

Can I take Fibre supplements and Metformin together?

Guía de interacción de medicamentos

Taking fibre supplements at the same time as metformin may slightly lower the amount of medicine your body absorbs. This could potentially make the metformin a little less effective at controlling your blood sugar levels.

Videos seleccionados para Interacciones de medicamentos

Continúa leyendo abajo

Por qué sucede esto

Fibre supplements (like psyllium husk or glucomannan) work by soaking up water and forming a gel in your gut. This gel can trap the metformin molecules, slowing down or reducing the amount of medicine that passes through your intestinal wall into your bloodstream.

You do not need to stop taking either, but it is best to separate the doses. Try to take your metformin at least 2 hours before or 4 to 6 hours after taking a fibre supplement. Always monitor your blood sugar levels regularly and speak to your doctor if you notice your readings are consistently higher than usual.

Continúa leyendo abajo

Severe kidney or liver problems

You must not take metformin if you have severe kidney or liver failure, as this significantly increases the risk of lactic acidosis, a rare but life-threatening build-up of acid in the blood.

Choking and intestinal blockage

You must take fibre supplements with a full glass of water (at least 200ml). Taking them without enough liquid can cause the supplement to swell and block your throat or oesophagus, leading to choking or bowel obstruction.

Drug absorption interference

Fibre can prevent other medicines from being absorbed properly. Take your other medications at least 1 hour before or 2 to 4 hours after taking a fibre supplement.

Lactic acidosis risk (Dehydration)

If you develop severe vomiting, diarrhoea, or a high fever, stop taking metformin and contact a doctor immediately. These conditions can lead to severe dehydration, which significantly increases the risk of a rare but life-threatening build-up of acid in the blood (lactic acidosis).

Contrast dye scans (e.g., CT or X-ray)

You must tell your doctor you take metformin if you are having a scan involving an injection of 'contrast dye'. You will usually need to stop taking metformin 48 hours before and after the procedure to prevent kidney damage.

Alcohol

It is best to avoid or strictly limit alcohol when taking these supplements. Alcohol can contribute to dehydration, which increases the risk of the supplement causing constipation or a bowel blockage.

It is best to avoid or strictly limit alcohol while taking metformin. Combining alcohol with metformin increases the risk of a rare but serious condition called lactic acidosis (a build-up of lactic acid in the blood). It also increases the risk of low blood sugar (hypoglycaemia).

Water and fluids

You must drink plenty of water (at least 200ml per dose) when taking fibre supplements. If you do not drink enough fluid, the supplement can cause a blockage in your intestine or throat.

Vitamin B12 (Dietary sources)

Long-term use of metformin can lower your vitamin B12 levels. Ensure you eat foods rich in B12 (such as meat, fish, and dairy) or speak to your doctor about monitoring your levels.

Continúa leyendo abajo

¿Tomas múltiples medicamentos? Nuestro Verificador de Interacciones de Medicamentos te ayuda a verificar si tus recetas, medicamentos de venta libre y suplementos son seguros para tomar juntos. Simplemente busca tus medicamentos para ver posibles interacciones y qué hacer al respecto.

Descargo de responsabilidad

Esta información es solo para fines educativos generales y no debe considerarse como un sustituto del consejo médico profesional. Siempre consulte a su médico de cabecera, farmacéutico u otro profesional de la salud calificado antes de tomar decisiones sobre sus medicamentos. Las circunstancias individuales pueden variar, y solo un profesional de la salud que conozca su historial médico puede proporcionar orientación personalizada.

Continúa leyendo abajo

Historial del artículo

La información en esta página está escrita y revisada por pares por clínicos calificados.

  • 25 Ene 2026 | Publicado originalmente
flu eligibility checker

Pregunta, comparte, conecta.

Navega por discusiones, haz preguntas y comparte experiencias en cientos de temas de salud.

symptom checker

¿Te sientes mal?

Evalúa tus síntomas en línea de forma gratuita

Suscríbete al boletín de Patient

Tu dosis semanal de consejos de salud claros y confiables, escritos para ayudarte a sentirte informado, seguro y en control.

Por favor, introduce una dirección de correo electrónico válida

Al suscribirte aceptas nuestros Política de Privacidad. Puedes darte de baja en cualquier momento. Nunca vendemos tus datos.