What adverse effect of oral contraceptives should lead a client to immediately stop taking the medication and contact a healthcare provider?

Visual disturbances are a critical adverse effect of oral contraceptives that warrant immediate cessation of the medication and consultation with a healthcare provider. This symptom may indicate a serious underlying condition, such as an increased risk of venous thromboembolism or other cardiovascular issues. Changes in vision can also signify potential complications like ocular migraines or vascular occlusion, which require prompt medical evaluation to prevent significant health risks, including permanent vision loss.

While side effects like weight gain, nausea, and skin rash can indeed occur with oral contraceptive use, they are typically not as urgent or severe as visual disturbances. Weight gain and nausea may be uncomfortable and need management but do not usually pose an immediate threat to health. Skin rash might require attention to rule out allergy or sensitivity, but it is not prioritized in the same way as symptoms that affect sight. Therefore, the presence of visual disturbances necessitates immediate medical intervention.