Topiramate side effects and when to seek help

Common side effects of topiramate

The following side effects of topiramate are usually mild. However, if they affect a person’s daily functioning and quality of life, they should talk with their doctor.

Tingling sensations

Many people experience a numbing, burning, or tingling feeling (parasthesia), particularly in their hands and feet. This is one of the most frequently reported side effects of topiramate.

Weight loss and loss of appetite

Topiramate often causes people to lose their appetite, which may lead to weight loss. Doctors suggest people eat at their usual meal times even if they do not feel hungry.

Sickness and diarrhea

Digestive issues like nausea, stomach pain, and diarrhea are fairly common with topiramate. To cope with nausea, stick to simple meals and avoid rich foods. For diarrhea, drink plenty of water to avoid dehydration.

Dizziness and fatigue

Fatigue and dizziness may occur with topiramate, especially when someone first starts the drug. If a person feels dizzy, they should sit or lie down until they feel better, and avoid driving or operating heavy machinery.

Changes in taste

People may notice a change in their sense of taste. Familiar foods or drinks may taste different or unusual during treatment.

Cognitive and speech problems

Topiramate can cause confusion, difficulty concentrating, and general memory issues. People may have word-finding difficulties or other language problems.

Nervousness or mood changes

Feeling nervous, anxious, irritable, or depressed are common psychological side effects associated with topiramate.

Experiencing side effects? After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews its side effects. If you develop a side effect while taking this medication and want to report it to the FDA, you can visit MedWatch or call 800-FDA-1088.

Serious side effects of topiramate

Some side effects of topiramate are severe and require immediate medical attention.

Metabolic acidosis

Topiramate can cause metabolic acidosis, a condition in which the blood becomes too acidic due to reduced bicarbonate levels. Symptoms include feeling very tired, hyperventilation (breathing fast), and an irregular heartbeat.

Eye Problems

Topiramate can cause acute myopia (nearsightedness) and secondary angle closure glaucoma. Symptoms include a sudden decrease in vision and intense eye pain, typically occurring within the first month of treatment. If left untreated, this can lead to permanent vision loss.

Kidney Stones

Topiramate is a carbonic anhydrase inhibitor, which means it naturally increases the risk of kidney stones. In clinical trials, adults treated with topiramate were 2 to 4 times more likely to develop kidney stones than people not taking the drug.

Suicidal thoughts

Antiepileptic drugs can affect mental health and may increase the risk of suicidal thoughts and behaviors. This occurred in about 1 in 500 people during clinical trials.

High blood ammonia

Topiramate can cause high ammonia levels in the blood, leading to brain dysfunction (encephalopathy) that causes extreme lethargy and vomiting.

Side effects in other populations

Topiramate may cause specific side effects in infants exposed to topiramate in the uterus and in children taking topiramate.

Pregnancy

Taking topiramate during pregnancy could harm a developing fetus.

In pregnancy registries, infants exposed to topiramate during the first trimester had a 1.4% prevalence of oral clefts, such as a cleft lip or palate, compared to 0.11% of infants without topiramate exposure.

In addition, 19.7% of newborns exposed to topiramate were small for their gestational age, compared to 5.4% of newborns without exposure.

Children

Long-term use of topiramate in children can decrease bone mineral density, leading to weaker bones. It can also slow down a child’s growth.

Children taking topiramate are also more susceptible to decreased sweating (hypohidrosis), which can cause their body temperature to rise dangerously high in warm weather.

How to reduce the risk of side effects

People can take the following steps to minimize severe side effects of topiramate:

• Drink plenty of fluids: Staying well-hydrated is crucial for preventing dehydration and reducing the risk of kidney stones.
• Avoid extreme heat: Because topiramate can prevent normal sweating, avoiding extreme heat can help prevent high fevers and overheating.
• Avoid alcohol: Mixing alcohol with topiramate can worsen tiredness and dizziness.
• Avoid a ketogenic diet: A high fat, low carbohydrate diet increases the risk of metabolic acidosis and kidney stones.
• Follow dosage instructions carefully: To lower the chance of cognitive side effects, doctors usually start patients on a low dose and gradually increase it over time.
• Do not stop taking topiramate suddenly: This may cause severe and uncontrollable seizures.

When to seek help for side effects of topiramate

A person should talk with a doctor if common side effects like nausea or dizziness do not wear off after a few weeks.

Call 911 or the local emergency number in the following situations:

• sudden vision changes
• intense back or side pain
• cloudy or smelly urine
• worsening depression or suicidal thoughts
• skin blisters, rash, or peeling skin
• serious allergic reaction, such as:
  • swelling of the lips, mouth, or throat
  • trouble breathing
  • skin turning pale, blue, or gray

Summary

Topiramate can help manage seizures and prevent severe migraines, but it has a wide range of possible side effects.

Common, mild side effects include a tingling feeling in the hands and feet, fatigue, nausea, and loss of appetite. Serious side effects include vision loss, metabolic acidosis, and kidney stones.

By staying hydrated, carefully monitoring for any physical or mental changes, and reporting severe symptoms to a doctor, patients can manage their treatment safely.