Vidalista 10 mg contains tadalafil, a PDE-5 inhibitor used for erectile dysfunction. It is not a muscle relaxant. However, tadalafil can have a mild smooth-muscle–relaxing effect on blood vessels. By increasing nitric-oxide/cGMP signaling, it relaxes vascular smooth muscle and increases blood flow. This is part of how it helps produce an erection. It generally does not significantly relax skeletal muscles (such as the muscles in your arms, legs, or back), so it shouldn't be expected to relieve muscle stiffness, spasms, or soreness. You may experience back pain or muscle aches as a side effect in some cases, usually within several hours after tadalafil and often resolving within about 48 hours. If you're asking because you noticed unusual muscle relaxation, weakness, or difficulty walking after taking 10 mg, tell me what you experienced and when it started.