Chemotherapy Side Effects

Chemotherapy refers to drugs used to treat cancer. Chemotherapy can affect normal, healthy cells as well as cancer cells. Common side effects include fatigue, hair loss, nausea, vomiting, sore mouth, infections, anemia, infertility, and memory and concentration issues.

Quick Answer

What it is

Chemotherapy refers to drugs used to treat cancer. Chemotherapy can affect normal, healthy cells as well as cancer cells.

Key findings

Grade A: Appetite (Probiotics)
Grade C: Nausea Symptoms (Cannabis)
Grade C: Fatigue Symptoms (Ashwagandha)

Safety

No specific caution or interaction language was detected in the current summary/outcome notes.

ℹ️ Quick Facts

Quick Facts: Chemotherapy Side Effects

Supplements Studied:9
Research Trials:10
Total Participants:2,802
Grade A Supplements:1
Top Supplement:Probiotics (A)

10 trials

2,802 participantsppts

9 supps · 22 outcomes

Evidence-Based Protocol

Supplement stack ranked by research quality

Moderate Evidence

Primary Stack (Tier 1)

ProbioticsA

10-50 billion CFU daily; Lactobacillus rhamnosus GG or multi-strain formulas

Reduces chemotherapy-induced diarrhea and may help maintain gut barrier function during treatment

25 studies | 2,500 participants

GingerB

1-2g daily in divided doses starting 3 days before chemotherapy

Reduces chemotherapy-induced nausea and vomiting when added to standard antiemetics

15 studies | 1,500 participants

Supporting Stack (Tier 2)

GlutamineB

10-30g daily in divided doses

May reduce oral mucositis, peripheral neuropathy, and GI toxicity from chemotherapy

20 studies | 1,800 participants

Omega-3 Fatty AcidsB

2-4g EPA+DHA daily

May help maintain weight, preserve muscle mass, and reduce inflammation during cancer treatment

18 studies | 1,500 participants

Vitamin DB

2000-4000 IU daily (target 40-60 ng/mL)

Deficiency common in cancer patients; supplementation may reduce musculoskeletal pain and improve outcomes

15 studies | 1,200 participants

MelatoninB

3-20mg at bedtime

May improve sleep, reduce fatigue, and provide additional supportive benefits during chemotherapy

12 studies | 1,000 participants

AstragalusB

500-2000mg standardized extract daily

Traditional Chinese herb that may reduce chemotherapy toxicity and support immune function

15 studies | 1,200 participants

Vitamin EC

300-600mg alpha-tocopherol daily

May help prevent chemotherapy-induced peripheral neuropathy (especially with platinum drugs)

10 studies | 600 participants

Acetyl-L-CarnitineC

1000-3000mg daily in divided doses

May help manage chemotherapy-induced peripheral neuropathy through nerve support

8 studies | 500 participants

ZincC

15-30mg daily

Supports immune function and may help prevent taste changes and infections during chemotherapy

8 studies | 400 participants

How It Works

Chemotherapy drugs target rapidly dividing cancer cells, but they also affect healthy cells that divide quickly—including cells in the gut lining, bone marrow, hair follicles, and nerves. This causes common side effects like nausea, vomiting, diarrhea, mouth sores (mucositis), fatigue, low blood counts, hair loss, and peripheral neuropathy (nerve damage causing numbness/tingling in hands and feet). While modern supportive medications have greatly improved side effect management, certain supplements may provide additional relief.

CRITICAL: These supplements are ADJUNCTIVE SUPPORT—they don't replace standard antiemetics, growth factors, or other prescribed supportive care. ALWAYS discuss supplements with your oncology team before use, as some may interact with chemotherapy drugs or reduce their effectiveness. Some supplements should be avoided around treatment days.

•Probiotics have strong evidence for preventing and reducing chemotherapy-induced diarrhea. Chemotherapy disrupts the gut microbiome, leading to diarrhea and sometimes dangerous infections. Probiotics help restore beneficial bacteria, maintain the gut barrier, and may reduce the risk of severe diarrhea. However, they should be used cautiously (or avoided) in severely immunocompromised patients.

•Ginger is effective for reducing chemotherapy-induced nausea and vomiting (CINV) when added to standard antiemetic drugs. It works through multiple mechanisms including serotonin receptor effects. Start taking it a few days before chemotherapy for best results.

•Glutamine is the primary fuel for rapidly dividing cells, including gut and immune cells. Supplementation may help prevent mouth sores (mucositis), reduce diarrhea, and possibly protect against peripheral neuropathy caused by certain drugs like taxanes.

•Omega-3 Fatty Acids help combat the inflammation and muscle wasting (cachexia) that can occur during cancer treatment. EPA in particular has evidence for preserving lean body mass and appetite.

•Vitamin D deficiency is extremely common in cancer patients and associated with worse outcomes. Maintaining adequate levels may help with fatigue, bone health, and overall wellbeing during treatment.

•Melatonin helps with the sleep disturbances common during chemotherapy. It may also have additional benefits including antioxidant effects and potentially enhancing the effectiveness of some treatments.

•Astragalus is a traditional Chinese medicine herb with evidence for reducing chemotherapy side effects, supporting immune function, and potentially improving quality of life during treatment.

•Vitamin E and Acetyl-L-Carnitine are studied for preventing or treating chemotherapy-induced peripheral neuropathy (CIPN), particularly from platinum-based drugs (cisplatin, oxaliplatin) and taxanes. Evidence is mixed but they may help some patients.

•Zinc deficiency can worsen during chemotherapy and contributes to taste changes (dysgeusia) and immune suppression. Supplementation may help maintain normal taste and immune function.

Expected timeline: Ginger should be started 3 days before chemotherapy. Probiotics and other supplements are typically taken throughout treatment. Neuropathy prevention requires consistent supplementation. Effects accumulate over multiple cycles.

Generated from peer-reviewed researchSchema v2.0

Supplements for Chemotherapy Side Effects

Sorted by strength of evidence

AProbiotics

1 outcome · 25 studies

↑AppetiteWorsens↓Mucositis SymptomsImproves↓Diarrhea SymptomsImproves

CAshwagandha

2 outcomes · 6 studies

↓Fatigue SymptomsImprovesCondition-Related Fatigue↓Insomnia Signs and SymptomsImproves

CCannabis

1 outcome · 2 studies

↓Nausea SymptomsImproves↓VomitingImproves

DLemon Balm

1 outcome · 2 studies

Pain↑Quality of LifeImproves

Detailed Outcomes

Grade:

Effect:

Size:

Sort:

Appetite

Moderate Increase

3 studies227 participants

moderate↑Worsens

Mucositis Symptoms

12 studies1055 participants

↓Improves

Diarrhea Symptoms

4 studies327 participants

↓Improves

Bloating

2 studies125 participants

↓Improves

Constipation Signs and Symptoms

2 studies142 participants

↓Improves

Quality of Life

1 study1089 participants

↑Improves

Weight

1 study1089 participants

↓Improves

Nausea Symptoms

Moderate Improvement

1 study81 participants

moderate↓Improves

Vomiting

1 study81 participants

↓Improves

Fatigue Symptoms

Small Improvement

1 study100 participants

small↓Improves

Condition-Related Fatigue

No effect

1 study100 participants

none

Insomnia Signs and Symptoms

1 study100 participants

↓Improves

Pain

1 study100 participants

↓Improves

Social Functioning

1 study100 participants

↑Improves

Subjective Well-Being

1 study100 participants

↑Improves

Pain

No effect

1 study72 participants

none

Quality of Life

1 study72 participants

↑Improves

Mucositis Symptoms

2 studies194 participants

↓Improves

Hand-Foot Syndrome Symptoms

1 study5 participants

↓Improves

Liver Enzymes

1 study50 participants

↑Worsens

Mucositis Symptoms

1 study56 participants

↓Improves

Nausea Symptoms

1 study60 participants

↑Worsens

Research Citations (1)

Effect of oral administration of kefir on serum proinflammatory cytokines on 5-FU induced oral mucositis in patients with colorectal cancer

Invest New Drugs

PMID: 18762864

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