Which medication is an example of a muscle relaxant?

Cyclobenzaprine is classified as a muscle relaxant, primarily used to relieve muscle spasms resulting from conditions such as strains or injuries. It works by acting on the central nervous system to produce sedation and reduce muscle activity. This mechanism helps alleviate discomfort associated with muscle spasms.

In contrast, ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that reduces pain and inflammation but does not specifically target muscle relaxation. Alendronate is a bisphosphonate used to treat osteoporosis, focusing on bone health rather than muscle conditions. Tamoxifen is a selective estrogen receptor modulator (SERM) primarily used in breast cancer treatment, without any indication for muscle relaxation. Thus, cyclobenzaprine stands out as the specific medication for muscle relaxation among the options provided.