Bio-Combination 21 (Bio 21)** is a homeopathic tablet formulated to support conditions related to the body’s calcium needs, particularly for bone and teeth health. It is often used in cases of general weakness in children, teens, or adults who may need additional support for calcium absorption and metabolism.

**Key ingredients** typically include:

1. **Calcarea Phosphorica (Calcium Phosphate)** – Promotes bone growth and assists with calcium absorption.
2. **Calcarea Fluorica (Calcium Fluoride)** – Strengthens teeth and bone surfaces and helps with tissue elasticity.
3. **Silicea (Silica)** – Supports bone strength and skin health.
4. **Magnesia Phosphorica (Magnesium Phosphate)** – Helps in relieving muscular pain and spasms.

This remedy is generally recommended to aid in improving bone health, strengthening teeth, and addressing issues like brittle nails, minor joint discomfort, and fatigue. Always consult a healthcare professional before beginning any new treatment.