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

Dhivy (carbidopa/levodopa) is an effective treatment for Parkinson's disease, but like all medications, it can cause side effects. Understanding what side effects are common, which ones require medical attention, and what to do in an emergency can help you stay safe and make the most of your treatment.

This guide covers Dhivy's full side effect profile based on FDA-approved prescribing information and clinical evidence — including the new 2026 vitamin B6 warning.

Common Side Effects of Dhivy

The most common side effects of Dhivy are shared by all carbidopa/levodopa formulations. These include:

• Dyskinesia (involuntary, uncontrolled movements of the face, arms, legs, or trunk): The most commonly reported adverse reaction. May appear or worsen as Dhivy doses are increased, or after years of treatment. Tell your doctor if these movements are bothersome — dose adjustments may help.
• Nausea: Often occurs early in treatment, especially at higher doses. Usually improves over time. Taking Dhivy with food (a light snack) may help reduce nausea, though high-protein meals can reduce levodopa absorption.
• Orthostatic hypotension (dizziness upon standing): Dhivy can lower blood pressure, which may cause lightheadedness when you rise from sitting or lying down. Rise slowly and hold onto stable surfaces.
• Somnolence (drowsiness and sleepiness): Many patients experience fatigue or daytime drowsiness, particularly when starting therapy or increasing the dose.
• Wearing off (return of Parkinson's symptoms near the end of a dose): As Parkinson's progresses, the duration of effect of each dose may shorten. Your doctor may adjust your Dhivy dose schedule or add a COMT inhibitor.

Serious Side Effects: Call Your Doctor

Some side effects of Dhivy require prompt medical attention. Contact your healthcare provider if you experience any of the following:

• Sudden sleep attacks: Dhivy can cause patients to fall asleep suddenly, without warning, even while engaged in normal daily activities like driving. This may occur at any time, even more than a year after starting treatment. Do not drive or operate heavy machinery until you know how Dhivy affects you.
• Hallucinations and psychotic-like behavior: Seeing, hearing, or feeling things that aren't real. More common in older patients and those on higher doses. Usually presents early in treatment. Dose reduction may help.
• Impulse control disorders: Strong, difficult-to-control urges to gamble, spend money, have sex, or eat excessively. These compulsive behaviors can be serious. Tell your doctor if you or your caregiver notice unusual impulse-control changes.
• Depression and suicidal thoughts: Dhivy may cause or worsen depression. Tell your doctor immediately if you have thoughts of suicide or self-harm.
• Increased intraocular pressure: If you have glaucoma, Dhivy may increase pressure inside the eye. Your doctor will want to monitor your eye pressure regularly.
• Cardiac arrhythmias: Irregular heart rhythms have been reported with carbidopa/levodopa, particularly in overdose situations.

Emergency: Seek Immediate Medical Attention

Go to the emergency room or call 911 if you experience:

• High fever combined with muscle stiffness, especially if you've recently stopped or reduced Dhivy — this may indicate neuroleptic malignant syndrome, a medical emergency
• Severe confusion or loss of consciousness
• New or worsening seizures (may be linked to vitamin B6 deficiency per the 2026 FDA warning)
• Signs of stroke (sudden weakness on one side, face drooping, slurred speech, severe headache)

The 2026 FDA Warning: Vitamin B6 Deficiency

In March 2026, the FDA required updated safety labeling for all carbidopa/levodopa products including Dhivy. Long-term treatment can deplete vitamin B6 (pyridoxine) levels. Symptoms of B6 deficiency include depression, confusion, mouth sores (cheilosis), glossitis (inflamed tongue), and in severe cases — seizures that do not respond to standard antiepileptic medications.

Ask your doctor about checking your vitamin B6 levels, especially if you have been on Dhivy or other carbidopa/levodopa products for a long time or if you are on a higher dose.

Other Things to Watch For

• Dark urine or sweat: Dhivy can cause urine or sweat to appear darker than usual. This is not dangerous.
• False lab test results: Dhivy may cause a positive Coombs test, false-positive urinary ketones, or false-negative glucose oxidase test for blood sugar. Tell all healthcare providers and lab technicians that you take Dhivy.
• Skin changes / melanoma risk: Parkinson's disease itself is associated with a higher risk of melanoma. Have your skin checked regularly and report any unusual lesions to your doctor.

Managing Side Effects

Many Dhivy side effects can be managed through dose adjustment. Dhivy's unique four-segment design makes it easier to fine-tune your dose in small increments — which is one of the reasons it was developed. If you're experiencing side effects, don't stop taking Dhivy abruptly. Instead:

• Contact your neurologist to discuss dose adjustment (e.g., reducing by a quarter segment at a time)
• Keep a symptom diary to help your doctor understand when side effects occur relative to your dosing schedule
• Report all side effects to your healthcare team — even ones you think are minor

For more information on what to avoid while taking Dhivy, see our guide on Dhivy drug interactions. If you need help finding Dhivy at a pharmacy near you, use medfinder.