Which factor is least likely to affect a client's compliance with lithium therapy?

The least likely factor to affect a client's compliance with lithium therapy is the opinions of the client's friends regarding their need to take medication. While social support can play a role in a client’s overall mental health and attitude towards treatment, it is typically more influenced by personal or medical factors.

In the context of lithium therapy, clients are often more concerned with the direct effects of the medication on their well-being, such as how it impacts their energy levels or mood, which can significantly influence their motivation to adhere to the treatment. Furthermore, the necessity for consistent blood level monitoring is crucial in managing lithium therapy, as it helps prevent toxicity and ensures therapeutic effectiveness. Additionally, potential side effects are a major consideration for clients, as adverse reactions can lead to non-compliance.

In contrast, while social perceptions can impact mindset, they tend not to be as determining a factor in medication adherence compared to the physiological and monitoring needs related to the treatment itself.