Amantadine Dosage: How Much to Take and What to Watch For

If you’ve been prescribed amantadine, you probably wonder how much you should actually take. The good news is the dosing isn’t a mystery – it’s mostly based on why you’re using the drug, your age, and how your kidneys are working. Below we break down the typical numbers, safety pointers, and everyday tips to make sure you get the most benefit with the fewest hassles.

Standard dosing for common uses

For most adults treating Parkinson’s disease, doctors start with a low dose of 100 mg once daily. After a week or two they may bump it up to 200 mg once daily or split it into 100 mg twice a day. The goal is to find the smallest amount that eases stiffness and tremor.

If you’re using amantadine to shorten flu symptoms, the usual adult regimen is 200 mg on day one, followed by 100 mg daily for the next four days. That short course is enough to help your body fight the virus.

Children older than six can take amantadine for certain movement disorders, but the dose is calculated by weight – roughly 5 mg per kilogram per day, divided into two doses. Never give a child a dose meant for an adult.

Kidney function matters

Amantadine leaves the body mainly through the kidneys. If you have reduced kidney function, the drug can build up and cause more side effects. In mild kidney impairment, doctors usually cut the dose by about 25 %. For moderate to severe problems, they might prescribe 50 mg once daily or even recommend a different medication altogether.

Because kidney function can change over time, it’s smart to have your doctor check your labs every few months if you stay on amantadine long‑term.

How to take it safely

Swallow the tablet whole with a glass of water. You can take it with food or on an empty stomach – it doesn’t really matter, but a meal can help if you get stomach upset.

If you miss a dose, take it as soon as you remember — but only if it’s more than six hours before your next scheduled dose. Skipping a double‑up can increase the risk of dizziness or heart palpitations.

Watch for common side effects like dry mouth, insomnia, or mild nausea. More serious signals – such as sudden swelling of the legs, severe confusion, or rapid heartbeat – need a doctor’s call right away.

When to talk to your doctor

Any new medication can interact with what you’re already taking. Tell your doctor if you’re on antihypertensives, antidepressants, or drugs that affect the heart rhythm. Adjustments may be needed.

Pregnant or breastfeeding women should avoid amantadine unless the doctor says the benefits outweigh the risks. There isn’t enough safety data to recommend it freely during pregnancy.

Finally, never change your dose on your own. Even if you feel great, cutting back too quickly can cause a rebound of symptoms.

Bottom line: the right amantadine dose is a balance between your condition, your age, and your kidney health. Follow your doctor’s prescription, keep an eye on side effects, and stay in touch with your healthcare team for any tweaks. With the proper dosing, amantadine can be a useful tool without causing unnecessary trouble.