Along with its needed effects, labetalol may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Although not all of these side effects may occur, if they do occur they may need medical attention. Side Effects. Drug information provided by: IBM Micromedex. Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Some less common side effects of this drug are, heartburn or indigestion, shortness of breath, blurred vision, unusual swelling of the face, legs, and fingers, chills, dry eyes, and erectile dysfunction (in men). SIDE EFFECTS. Most adverse effects are mild and transient and occur early in the course of treatment. In controlled clinical trials of 3 to 4 months' duration, discontinuation of Trandate (labetalol) Tablets due to one or more adverse effects was required in 7% of all patients. SIDE EFFECTS. Most adverse effects are mild and transient and occur early in the course of treatment. In controlled clinical trials of 3 to 4 months' duration, discontinuation of Trandate (labetalol) Tablets due to one or more adverse effects was required in 7% of all patients. Labetalol oral tablet (Trandate) is used to treat high blood pressure (hypertension). Learn about side effects, warnings, dosage, and more. Learn about side effects, warnings, dosage, and more. Find patient medical information for Labetalol Oral on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings. Patients taking labetalol for high blood pressure typically tolerate it well, but there are several common side effects they may experience, particularly at higher doses. Some people will have digestive problems like nausea, heartburn , and diarrhea after taking their medication. Side Effects and Risks of taking Labetalol during Pregnancy It has been generally observed that older adults are more sensitive to the side effects of the drug. It is not necessary that some side effect will definitely occur, but if it occurs, it may need medical attention. Along with its needed effects, labetalol (the active ingredient contained in Trandate) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.