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

Starting a new cancer medication is understandably nerve-wracking, and knowing what side effects to expect with Phyrago (dasatinib) can help you feel more prepared and know when to seek help. Phyrago is an effective treatment for certain leukemias, but it does come with a range of potential side effects — some common and manageable, and some that require immediate medical attention.

This guide reviews the most important Phyrago side effects based on the FDA-approved prescribing information, what to watch for, and when to call your oncology team.

Most Common Side Effects of Phyrago (Occurring in ≥15% of Patients)

In clinical trials, the most common side effects reported in at least 15% of patients taking dasatinib as single-agent therapy were:

• Myelosuppression (low blood cell counts): Includes low red blood cells (anemia), low white blood cells (neutropenia), and low platelets (thrombocytopenia). Your oncology team will monitor your blood counts regularly.

• Fluid retention: Swelling in the legs, hands, or face; weight gain; shortness of breath from fluid around the lungs (pleural effusion). This can be mild or occasionally severe.

• Diarrhea: Often manageable with anti-diarrheal medications. Tell your doctor if it is frequent, watery, or prevents you from staying hydrated.

• Headache: Common, usually mild to moderate.

• Skin rash: Most rashes are mild. Severe skin reactions are rare but require prompt medical evaluation (see serious side effects below).

• Bleeding / hemorrhage: Easy bruising, unusual bleeding. Can be mild (bruising) to serious (internal bleeding). Report any unusual bleeding to your oncologist promptly.

• Dyspnea (shortness of breath): May be related to fluid retention or low red blood cell counts. Report new or worsening shortness of breath promptly.

• Fatigue: Very common with cancer treatment. Balance rest with gentle activity as tolerated.

• Nausea: Taking Phyrago with food can help reduce nausea.

• Musculoskeletal pain: Muscle aches, joint pain. Usually manageable.

Serious Side Effects: Call Your Doctor Immediately

Some Phyrago side effects are serious and require urgent medical evaluation. Contact your oncologist or go to the emergency room if you experience:

• Fever, chills, or signs of infection — With low white blood cell counts, infections can be severe and life-threatening.

• Unusual or severe bleeding — bright red or dark/tarry stools, blood in urine, severe bruising, or any unexplained bleeding.

• Shortness of breath, dry cough, or chest pain with breathing — These can signal pleural effusion (fluid around the lungs), which may require dose modification or drainage.

• Signs of pulmonary arterial hypertension (PAH): Increasing breathlessness, fatigue with exertion, and leg swelling can signal PAH. Phyrago may need to be permanently discontinued if PAH is confirmed.

• Fast or irregular heartbeat, dizziness, or fainting — May signal QT interval prolongation or cardiac arrhythmia.

• Severe skin reactions — Blistering, peeling, sores in mouth or eyes can indicate Stevens-Johnson syndrome, a rare but serious dermatologic reaction.

• Jaundice, dark urine, or upper abdominal pain — May signal hepatotoxicity (liver damage). Your doctor will monitor liver enzymes monthly.

Pregnancy and Reproductive Risks

Phyrago can cause serious fetal harm (embryo-fetal toxicity). Women of childbearing age must use effective contraception during treatment and for 30 days after the last dose. Men with female partners who could become pregnant should also use effective contraception during treatment and for 30 days after the last dose. Breastfeeding is not recommended during Phyrago treatment and for 2 weeks after the last dose.

Tips for Managing Common Side Effects

• Take Phyrago with food if nausea is a problem (it can be taken with or without food)

• Weigh yourself daily to monitor for fluid retention (sudden weight gain can signal fluid accumulation)

• Avoid grapefruit and grapefruit juice, which can increase dasatinib levels

• Keep all blood test appointments — blood counts must be monitored regularly (every 2 weeks for 12 weeks, then every 3 months in chronic phase CML)

See also our guide to Phyrago drug interactions for a full list of medications to avoid. If you need help finding your Phyrago prescription, visit medfinder.com.