Is appetite loss a common side effect of bladder cancer treatment? How to manage it

Appetite loss is fairly common in bladder cancer and during its treatments, and it can be managed with practical nutrition strategies and, when needed, medical support. ^[1] Appetite loss is noted across patient education for common bladder cancer therapies, including antibody–drug conjugates and immunotherapy. ^{[2] [3]} It’s also a frequent side effect during cancer care in general, so proactive steps can help maintain weight, strength, and energy. ^{[4] [5]}

Why appetite loss happens

• Cancer itself can reduce hunger and make eating uncomfortable, contributing to weight loss. ^[1]
• Treatments (such as enfortumab vedotin or combinations with pembrolizumab, and other immunotherapies) often affect taste, mouth/throat comfort, fatigue, and nausea, all of which can lower appetite. ^{[2] [3]}
• Low appetite during cancer treatment is widely recognized and addressed with supportive nutrition guidance. ^{[4] [5]}

First-line nutrition strategies

• Eat small, frequent meals or snacks rather than three large meals; setting a schedule (for example, every 2 hours) can help you eat even when you’re not hungry. ^[5]
• Take advantage of times you feel more hungry many people find mornings best and eat more during those windows. ^{[4] [6] [7]}
• Limit fluids at mealtimes so drinks don’t fill you up; have most liquids at least 30 minutes before or after meals. ^{[4] [6] [7]}
• Choose calorie- and protein-dense foods to maintain weight and muscle, adding extras like nut butters, cheese, eggs, and healthy oils to meals. ^[8]
• Use high-calorie, high-protein shakes or instant drink mixes if solid food is difficult; smoothies with yogurt or milk are convenient options. ^[9]
• Create a pleasant mealtime setting soft music, comfortable seating to make eating easier and more appealing. ^[6]
• If reduced intake lasts more than a few days, ask your care team whether a multivitamin is appropriate, as supplements can interact with treatments. ^[10]

Practical tips at home

• Keep ready-to-eat snacks (trail mix, cheese, yogurt, bananas) within easy reach and eat by the clock rather than waiting for hunger. ^[5]
• Prioritize protein at each mini‑meal to support recovery and strength. ^[8]
• If mouth or throat discomfort limits eating, ask your team for strategies to manage these symptoms early. ^{[2] [3]}
• Gentle, approved activity can sometimes stimulate appetite; confirm safety with your clinician before starting. ^[9]

When to involve your care team

• Tell your doctor or nurse if appetite loss persists, if you’re losing weight, or if eating becomes difficult, and ask for a dietitian referral. ^{[2] [3] [11]}
• Nutrition counseling during treatment is recommended to tailor calorie, protein, and hydration needs and to manage side effects that interfere with eating. ^{[8] [5]}

Medical options for severe loss of appetite

For ongoing weight loss or cancer-related anorexia (loss of desire to eat), clinicians may consider prescription appetite stimulants after evaluating risks and benefits; one commonly used option is megestrol acetate, which has shown weight gain benefits in cancer anorexia/cachexia. ^[12] Decisions about medications should be individualized with your oncology team. ^[12]

Bottom line

• Appetite loss is common in bladder cancer and its treatments, and it can lead to weight loss if not addressed. ^{[1] [2] [3]}
• Consistent, small, high‑calorie, high‑protein meals; timing fluids; and nutrition shakes are practical first steps. ^{[4] [6] [9] [5]}
• Early communication with your care team and dietitian is important, and medical appetite stimulants may be considered for persistent anorexia and weight loss. ^{[11] [8] [12]}