Appetite loss and weight loss
You may not feel hungry or may feel full quickly. Over time, this can lead to weight loss and less strength.
Why it happens
Chemotherapy, radiation, immunotherapy, and the cancer itself can all lower appetite. Nausea, taste changes, mouth sores, pain, and sadness can make it worse.
What helps
- Eat small meals or snacks every 2 to 3 hours instead of waiting until you are hungry.
- Choose foods high in calories and protein, like eggs, nut butter, cheese, and shakes.
- Keep easy snacks nearby so you can eat without cooking.
- Drink fluids between meals, not with them, so you do not fill up too fast.
- Eat more at the time of day when you feel best.
- Ask to meet with an oncology dietitian.
Call your care team right away if you have
- You lose weight without trying, such as 5 pounds or more in a month.
- You cannot eat or drink much for more than a day or two.
- You feel weak or dizzy.
Questions to ask
- Can I see a dietitian who works with people who have cancer?
- Would a nutrition drink or an appetite medicine help me?
- What weight change should I report to you?
Medicines that can cause this
- Adagrasib
- Apalutamide
- Aprepitant and fosaprepitant
- Asparaginase (pegaspargase and others)
- Axitinib
- Azacitidine
- Bendamustine
- Bortezomib
- Busulfan
- CAR T-cell therapy
- Cabozantinib
- Capecitabine
- Capmatinib
- Cisplatin
- Cladribine
- Cyclophosphamide
- Dacarbazine
- Datopotamab deruxtecan
- Elotuzumab
- Elranatamab
- Enfortumab vedotin
- Enzalutamide
- Erlotinib
- Ifosfamide
- Ivosidenib
- Lenvatinib
- Lurbinectedin
- Mercaptopurine (6-MP)
- Nab-paclitaxel (paclitaxel protein-bound)
- Olanzapine (for nausea)
Sources
Quick answers
- What is appetite loss and weight loss during cancer treatment?
- You may not feel hungry or may feel full quickly. Over time, this can lead to weight loss and less strength.
- Why does appetite loss and weight loss happen?
- Chemotherapy, radiation, immunotherapy, and the cancer itself can all lower appetite. Nausea, taste changes, mouth sores, pain, and sadness can make it worse.
- What helps with appetite loss and weight loss?
- Eat small meals or snacks every 2 to 3 hours instead of waiting until you are hungry; Choose foods high in calories and protein, like eggs, nut butter, cheese, and shakes; Keep easy snacks nearby so you can eat without cooking; Drink fluids between meals, not with them, so you do not fill up too fast; Eat more at the time of day when you feel best; Ask to meet with an oncology dietitian.
- When should I call my care team about appetite loss and weight loss?
- You lose weight without trying, such as 5 pounds or more in a month; You cannot eat or drink much for more than a day or two; You feel weak or dizzy.
Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.