Valsartan is an angiotensin II receptor blocker (ARB) that works by blocking a substance in the body that causes blood vessels to tighten. This action allows blood vessels to relax and widen, which lowers blood pressure. Lowering blood pressure reduces the workload on the heart, making it easier to pump blood. The 320 mg strength is the maximum recommended daily dose, prescribed when lower doses do not achieve the desired therapeutic outcome.
Conditions Treated with the 320 mg Dose
The 320 mg daily dose of valsartan is reserved for managing conditions that have not responded adequately to lower doses. For individuals with high blood pressure (hypertension), this maximum dose is used when lower doses fail to bring blood pressure to the target level. The full antihypertensive effect is seen within four weeks of starting therapy, and dose adjustments are made based on this response.
This higher dosage is also a standard part of treatment for certain patients with heart failure. In this context, valsartan helps to alleviate the strain on a weakened heart muscle. By lowering the pressure against which the heart has to pump, the 320 mg dose can improve symptoms and has been shown to reduce the risk of hospitalization for heart failure. The total daily dose for heart failure is often split into 160 mg taken twice daily.
Following a heart attack (myocardial infarction), valsartan can be a component of a patient’s long-term care plan. For stable patients who have experienced left ventricular dysfunction after a heart attack, the 320 mg daily dose has been shown to improve survival rates. Treatment may begin as early as 12 hours after the event, starting with a low dose and gradually titrating up to a target maintenance dose to reduce the risk of future cardiovascular events.
Proper Administration and Precautions
To ensure consistent levels, valsartan should be taken at the same time each day. It can be administered with or without food. For hypertension, it is taken once daily, while for heart failure or post-heart attack care, the total daily dose is often divided and taken twice a day.
If a dose is missed, it should be taken as soon as it is remembered. However, if it is nearly time for the next scheduled dose, the missed one should be skipped to avoid taking a double amount. Doubling the dose can increase the risk of adverse effects and does not improve the medication’s efficacy.
Certain precautions are necessary while taking valsartan. The medication can increase potassium levels in the blood, so it is important to avoid potassium supplements and salt substitutes that contain potassium unless directed by a doctor. Staying well-hydrated is also advised, as dehydration can lead to a sharp drop in blood pressure, causing dizziness or fainting.
Interactions with other medications can occur. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, may reduce valsartan’s blood pressure-lowering effects and can increase the risk of kidney problems. Combining valsartan with other medications that lower blood pressure requires careful monitoring by a healthcare provider to prevent blood pressure from falling too low.
Potential Side Effects at a High Dosage
As the body adjusts to a lower blood pressure, some individuals may experience side effects such as dizziness, lightheadedness, or headaches. These effects are common when starting the medication or increasing the dose and often lessen over time. Persistent symptoms should be discussed with a healthcare provider, as they may indicate the need for a dose adjustment.
While less common, more serious side effects can occur and warrant immediate medical attention. Symptoms of high potassium levels (hyperkalemia) include nausea, muscle weakness, or a slow or irregular heartbeat. Any significant change in the amount of urine produced could signal a kidney issue. Fainting or severe dizziness are also reasons to seek prompt medical care.
Valsartan carries a warning from the FDA regarding its use during pregnancy. The medication can cause injury or death to a developing fetus and must not be used by anyone who is pregnant. Women planning to become pregnant should discuss alternative blood pressure treatments with their doctor. Effective birth control is recommended for women of childbearing potential while taking this medication.