Amphetamine Side Effects: What to Expect and When to Call Your Doctor

What You Need to Know About Amphetamine Side Effects

If you've recently started taking Amphetamine — or you're thinking about it — understanding the side effects can help you know what's normal and what's not. Most people tolerate Amphetamine well, but like all medications, it can cause unwanted effects.

This guide covers the common side effects you might experience, the serious ones to watch for, and when it's time to call your doctor.

What Is Amphetamine?

Amphetamine is a central nervous system (CNS) stimulant most commonly prescribed for ADHD and narcolepsy. It's available under brand names like Adderall, Adderall XR, Mydayis, Evekeo, and Dyanavel XR. It works by increasing dopamine and norepinephrine levels in the brain, which improves focus and attention.

Amphetamine is a Schedule II controlled substance, meaning it has legitimate medical uses but also carries a risk of dependence. Your doctor will monitor you carefully while you're taking it.

Common Side Effects

These side effects are reported frequently by people taking Amphetamine. They're usually mild and often improve after the first few weeks of treatment:

• Decreased appetite — This is one of the most common effects. Many people notice they're not hungry during the hours the medication is active.
• Insomnia — Difficulty falling or staying asleep, especially if you take your dose too late in the day.
• Dry mouth — A frequent complaint that can be managed with water, sugar-free gum, or lozenges.
• Headache — Usually mild and tends to improve over time.
• Nervousness or anxiety — Some people feel jittery or on edge, particularly at higher doses.
• Increased heart rate — You may notice your heart beats faster than usual.
• Weight loss — Related to decreased appetite; more common in the first few months.
• Stomach pain — Taking Amphetamine with food can help reduce this.
• Irritability — Some people experience mood changes, especially as the medication wears off.
• Restlessness — A feeling of being unable to sit still.
• Dizziness — Usually mild and temporary.

Serious Side Effects

While less common, some side effects of Amphetamine are serious and require immediate medical attention. Call your doctor or go to the emergency room if you experience any of the following:

Cardiovascular Events

Amphetamine carries an FDA boxed warning about the risk of serious cardiovascular events, including heart attack, stroke, and sudden death. This risk is higher in people with pre-existing heart conditions. Symptoms to watch for include:

• Chest pain or tightness
• Shortness of breath
• Fainting or near-fainting
• Irregular heartbeat

Increased Blood Pressure

Amphetamine can raise your blood pressure. Your doctor should check your blood pressure regularly while you're on this medication. If you notice severe headaches, blurred vision, or nosebleeds, let your doctor know.

Psychiatric Symptoms

In rare cases, Amphetamine can cause or worsen psychiatric symptoms, including:

• New or worsening psychosis (hallucinations, delusions, paranoia)
• Manic episodes
• Aggressive behavior

These are more likely at higher doses or in people with a history of mental health conditions.

Seizures

Amphetamine may lower the seizure threshold. If you have a history of seizures or epilepsy, discuss this with your doctor before starting treatment.

Peripheral Vasculopathy (Raynaud's Phenomenon)

Some people experience numbness, coolness, or color changes in their fingers or toes. This is caused by reduced blood flow to the extremities. Report these symptoms to your doctor promptly.

Serotonin Syndrome

If you take Amphetamine with other medications that increase serotonin — such as SSRIs, SNRIs, or triptans — there's a risk of serotonin syndrome. Symptoms include agitation, rapid heartbeat, high body temperature, muscle rigidity, and diarrhea. This is a medical emergency. Learn more about Amphetamine drug interactions.

Side Effects in Specific Populations

Children and Adolescents

In addition to the side effects listed above, children taking Amphetamine may experience growth suppression. Long-term use of stimulants has been associated with slower weight gain and height growth. Your child's doctor should monitor growth regularly and may recommend drug holidays during school breaks.

Pregnant and Breastfeeding Women

Amphetamine is classified as Pregnancy Category C. There may be risks to the fetus, so it should only be used during pregnancy if the benefits clearly outweigh the risks. Amphetamine is also excreted in breast milk and is not recommended while breastfeeding.

Older Adults

Older adults may be more sensitive to the cardiovascular effects of Amphetamine. Blood pressure and heart rate should be monitored closely.

How to Manage Common Side Effects

Many side effects can be reduced or managed with simple strategies:

• For decreased appetite: Eat a good breakfast before your first dose. Plan nutritious snacks for when the medication wears off in the evening.
• For insomnia: Take your medication early in the day. Avoid caffeine in the afternoon and evening. Practice good sleep hygiene.
• For dry mouth: Stay hydrated. Use sugar-free gum or candy. Consider an over-the-counter dry mouth rinse.
• For stomach pain: Take your medication with food.
• For headaches: Stay hydrated and get enough sleep. Over-the-counter pain relievers like acetaminophen can help.
• For nervousness: Talk to your doctor about lowering your dose. Avoid caffeine and other stimulants.

If side effects persist or become bothersome, don't stop taking your medication on your own. Talk to your doctor — they may adjust your dose, switch you to a different formulation (like extended-release instead of immediate-release), or try an alternative medication.

Final Thoughts

Most people who take Amphetamine experience mild side effects that improve over time. The key is knowing what to expect and staying in close communication with your doctor. If you notice anything unusual — especially chest pain, psychiatric symptoms, or signs of serotonin syndrome — don't wait. Call your doctor or go to the ER.

For more information, read our guides on what Amphetamine is and how Amphetamine works. If you're having trouble finding your medication, Medfinder can help you locate a pharmacy with Amphetamine in stock near you.