Biphasic current is characterized by which feature?

Biphasic current is characterized by which feature?

• A. A pulse with two phases; current flows in both directions.
• B. Direct current only.
• C. A pulse with multiple phases not limited to two.
• D. Current flowing in one direction.

Answer: (A)

Biphasic current consists of two phases with opposite polarity within a single stimulation pulse, so the current reverses direction during the pulse. This setup delivers a net zero charge per pulse, which helps prevent electrode polarization and tissue irritation, making it safer for therapeutic stimulation. That’s why it’s described as a pulse with two phases in which current flows in both directions. Direct current would keep the same polarity and flow in one direction, not alternating, so it’s monophasic. A pulse with multiple phases not limited to two is polyphasic, not biphasic. Current flowing in one direction is also monophasic.

Biphasic current consists of two phases with opposite polarity within a single stimulation pulse, so the current reverses direction during the pulse. This setup delivers a net zero charge per pulse, which helps prevent electrode polarization and tissue irritation, making it safer for therapeutic stimulation. That’s why it’s described as a pulse with two phases in which current flows in both directions.

Direct current would keep the same polarity and flow in one direction, not alternating, so it’s monophasic. A pulse with multiple phases not limited to two is polyphasic, not biphasic. Current flowing in one direction is also monophasic.