FIRST-Testosterone Side Effects

Generic name: testosterone

Medically reviewed by Drugs.com. Last updated on Feb 8, 2025.

Note: This document provides detailed information about FIRST-Testosterone Side Effects associated with testosterone. Some dosage forms listed on this page may not apply specifically to the brand name FIRST-Testosterone.

Applies to testosterone: nasal gel/jelly.

Other dosage forms:

• oral capsule liquid filled
• implant, oil, solution
• transdermal patch extended release

Serious side effects of FIRST-Testosterone

Along with its needed effects, testosterone (the active ingredient contained in FIRST-Testosterone) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking testosterone:

Other side effects of FIRST-Testosterone

Some side effects of testosterone may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Precautions

It is very important that your doctor check your progress while you are using this medicine. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it. Blood and urine tests may be needed to check for unwanted effects.

Do not use Natesto® together with other medicines given into your nose (eg, oxymetazoline), unless your doctor says it is okay.

This medicine should not be used by women. Testosterone may cause birth defects if a pregnant woman comes in contact with the medicine. Make sure your doctor knows if your sexual partner is pregnant. If a pregnancy occurs while you are using this medicine, tell your doctor right away.

This medicine may cause nasal problems. Check with your doctor right away if you have a runny nose, congestion, sneezing, nosebleeds, nasal discomfort, nasal scabbing, or nasal dryness while using this medicine.

This medicine may cause blood clotting problems. Check with your doctor right away if you have a chest pain, trouble breathing, coughing up blood, numbness or weakness in your arm or leg, or on one side of your body, or pain in your lower leg (calf) while using this medicine.

This medicine may increase your risk of having a heart attack or stroke. Tell your doctor right away if you have chest pain that may spread to your arms, jaw, back, or neck, faintness, headache, nausea, vomiting, trouble breathing, trouble seeing or speaking, or unusual sweating.

This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.

Tell your doctor if your female partner or child starts to have male-like body changes while you are using this medicine. Such changes may include hair growth on the face, a deeper voice, or a significant increase in acne. The changes may also include an enlarged penis or clitoris, early development of pubic hair, increased erections or sexual desire, aggressive behavior, and bone problems.

In some cases, this medicine may decrease the amount of sperm men make and affect their ability to have children. If you plan to have children, talk with your doctor before using this medicine.

Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellow eyes or skin. These could be symptoms of a serious liver problem.

This medicine may cause fluid retention (edema) in some patients. Tell your doctor right away if you have bloating or swelling of the face, arms, hands, lower legs, or feet, tingling of the hands or feet, or unusual weight gain or loss.

This medicine may affect the results of the prostate specific antigen (PSA) test, which may be used to detect prostate cancer. Make sure you tell all of your doctors that you are using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

For healthcare professionals

Applies to testosterone: buccal film extended release, compounding powder, intramuscular solution, nasal gel, oral capsule, subcutaneous implant, subcutaneous solution, transdermal cream, transdermal film, transdermal film extended release, transdermal gel, transdermal ointment, transdermal solution.

General adverse events

The most frequently reported side effects with this drug are edema, acne, site pain, injection site erythema, cough or dyspnea during or immediately after injection.

The most frequently reported side effects with testosterone (the active ingredient contained in FIRST-Testosterone) topical are skin reaction (16.1%) and allergic contact dermatitis (up to 37%).^[Ref]

Dermatologic

• Very common (10% or more): Testosterone topical: Skin reaction (16.1%), burn-like blisters (12%), itching, allergic contact dermatitis (up to 37%)
• Common (1% to 10%): Acne, induration, burning
• Uncommon (0.1% to 1%): Alopecia, erythema, rash (including rash popular), pruritus, dry skin, folliculitis (testosterone (the active ingredient contained in FIRST-Testosterone) topical)
• Frequency not reported: Seborrhea, urticaria, male pattern baldness, hirsutism injection site inflammation
• Postmarketing reports: Angioedema, angioneurotic edema, hyperhidrosis, discolored hair, leukocytoclastic vasculitis^[Ref]

Endocrine

• Very common (10% or more): Accelerated growth
• Common (1% to 10%): Increased estradiol, hypogonadism
• Uncommon (0.1% to 1%): Increased blood testosterone (the active ingredient contained in FIRST-Testosterone) Frequency not reported: Signs of virilization in women (e.g., hoarseness, acne, hirsutism, menstrual irregularity, clitoral enlargement, and alopecia), precocious puberty (in prepubertal males)
• Postmarketing reports: Hyperparathyroidism, prolactin increased, testosterone increased^[Ref]

Gastrointestinal

• Very common (10% or more): Testosterone buccal film: Gingivitis (32.6%)
• Common (1% to 10%): Diarrhea, oily stools (due to IM injection oily solvent); Testosterone topical: Gastroesophageal reflux disease, gastrointestinal bleeding, gum or mouth irritation (9.2%), taste bitter, gum pain, gum tenderness, gum edema, taste perversion
• Uncommon (0.1% to 1%): Nausea
• Rare (less than 0.1%): Abdominal pain
• Frequency not reported: Abdominal disorder, intraabdominal hemorrhage
• Postmarketing reports: Vomiting; Testosterone buccal film: Dry mouth, gingival swelling, lip swelling, mouth ulceration, stomatitis^[Ref]

The majority of gum-related adverse events were transient.^[Ref]

Local

• Very common (10% or more): Testosterone topical: Application site pruritus (up to 37%), application site blistering (12%)
• Common (1% to 10%): Injection site pain, injection site discomfort, injection site pruritus, erythema, injection site hematoma, injection site irritation, injection site inflammation; injection site reaction; Topical testosterone (the active ingredient contained in FIRST-Testosterone) Application site erythema, application site warmth, application site irritation, application site vesicles, application site exfoliation, application site burning, application site induration, bullae at application site, mechanical irritation at application site, rash at application site, contamination of application site
• Postmarketing reports: Injection site abscess, procedural pain, application site swelling (topical testosterone)^[Ref]

Cardiovascular

• Common (1% to 10%): Hot flush, hypertension
• Uncommon (0.1% to 1%): Cardiovascular disorder
• Frequency not reported: Venous thromboembolism
• Postmarketing reports: Angina pectoris, cardiac arrest, cardiac failure, coronary artery disease, coronary artery occlusion, myocardial infarction, tachycardia, cerebral infarction, cerebrovascular accident, circulatory collapse, deep venous thrombosis, syncope, thromboembolism, thrombosis, venous insufficiency, stroke^[Ref]

Genitourinary

• Common (1% to 10%): Abnormal prostate examination, benign prostate hyperplasia (BPH), ejaculation disorder, prostatitis
• Uncommon (0.1% to 1%): Prostate induration, prostatic disorder, testicular pain, decreased urine flow, urinary retention, urinary tract disorder, nocturia, dysuria
• Rare (less than 0.1%): Micturition disorders, epididymitis, bladder irritability, impotence, inhibition of testicular function and testicular atrophy
• Frequency not reported: Oligospermia, priapism, benign prostatic hyperplasia (prostatic growth to eugonadal state), excessive frequency and duration of erections; Pediatrics: Precocious sexual development, an increased frequency of erections, phallic enlargement
• Postmarketing reports: Prostate infection, calculus urinary, dysuria, hematuria, urinary tract disorder, pollakiuria, azoospermia^[Ref]

Hematologic

• Common (1% to 10%): Polycythemia, hematocrit increased
• Uncommon (0.1% to 1%): Increased red blood cell count, increased hemoglobin, prolonged activated partial thromboplastin time, prolonged prothrombin time
• Frequency not reported: Blood and lymphatic system disorders, suppression of clotting factors II, V, VII, and X, bleeding in patients on concomitant anticoagulant therapy
• Postmarketing reports: Thrombocytopenia, anemia^[Ref]

Metabolic

• Common (1% to 10%): Weight increased, appetite increased, fluid retention (sodium, chloride, water, potassium, calcium, and inorganic phosphates)
• Uncommon (0.1% to 1%): Increased glycosylated hemoglobin, hypercholesterolemia, increased triglyceride
• Frequency not reported: Abnormal lipids (decrease in serum LDL, HDL, and triglycerides), metabolism and nutrition disorders, hypercalcemia
• Postmarketing reports: Hypoglycemia, diabetes mellitus, fluid retention, hyperlipidemia, hypertriglyceridemia, blood glucose increased^[Ref]

Musculoskeletal

• Common (1% to 10%): Back pain, hemarthrosis (testosterone (the active ingredient contained in FIRST-Testosterone) topical)
• Uncommon (0.1% to 1%): Arthralgia, pain in extremity, muscle spasm, muscle strain, myalgia, musculoskeletal stiffness, increased creatine phosphokinase
• Frequency not reported: Pediatrics: Premature epiphyseal closure, increased bone formation
• Postmarketing reports: Musculoskeletal chest pain, musculoskeletal pain, myalgia, osteopenia, osteoporosis, systemic lupus erythematosus^[Ref]

Nervous system

• Common (1% to 10%): Headache, vertigo (topical testosterone (the active ingredient contained in FIRST-Testosterone)
• Uncommon (0.1% to 1%): Migraine, tremor, dizziness
• Frequency not reported: Nervousness, paresthesia
• Postmarketing reports: Cerebrovascular insufficiency, reversible ischemic neurological deficiency, transient ischemic attack, amnesia^[Ref]

Oncologic

• Common (1% to 10%): Prostatic specific antigen (PSA) increased, prostate cancer
• Uncommon (0.1% to 1%): Prostatic intraepithelial neoplasia
• Rare (less than 0.1%): Neoplasms benign, malignant, and unspecified (including cysts and polyps)^[Ref]

Other

• Common (1% to 10%): Fatigue, hyperhidrosis; chills, body pain, smell disorder
• Uncommon (0.1% to 1%): Breast induration, breast pain, sensitive nipples, gynecomastia, increased estradiol, increased testosterone (the active ingredient contained in FIRST-Testosterone) asthenia, night sweats
• Rare (less than 0.1%): Fever, malaise
• Frequency not reported: Edema
• Postmarketing reports: Sudden hearing loss, tinnitus, Influenza like illness^[Ref]

Psychiatric

• Common (1% to 10%): Irritability, insomnia, mood swings, aggression,
• Uncommon (0.1% to 1%): Depression, emotional disorder, restlessness, increased libido, decreased libido
• Frequency not reported: Hostility, anxiety
• Postmarketing reports: Korsakoff's psychosis nonalcoholic, male orgasmic disorder, restlessness, sleep disorder^[Ref]

Respiratory

• Common (1% to 10%): Sinusitis, nasopharyngitis, upper respiratory tract infection, bronchitis
• Uncommon (0.1% to 1%): Cough, dyspnea, snoring, dysphonia
• Rare (less than 0.1%): Pulmonary microembolism (POME) (cough, dyspnea, malaise, hyperhidrosis, chest pain, dizziness, paresthesia, or syncope) caused by oily solutions
• Frequency not reported: Sleep apnea
• Postmarketing reports: Chest pain, asthma, chronic obstructive pulmonary disease, hyperventilation, obstructive airway disorder, pharyngeal edema, pharyngolaryngeal pain, pulmonary embolism, respiratory distress, rhinitis, sleep apnea syndrome^[Ref]

Signs and symptoms of pulmonary microemboli may occur during or immediately after the injections and are reversible.^[Ref]

Hepatic

• Uncommon (0.1% to 1%): Abnormal LFT, increased AST
• Rare (less than 0.1%): Abnormal hepatic function
• Frequency not reported: Jaundice, benign liver tumor, malignant liver tumor, liver enlargement, peliosis hepatitis
• Postmarketing reports: ALT increased, AST increased, bilirubin increased, transaminases increased, gamma-glutamyltransferase increased^[Ref]

Hypersensitivity

• Uncommon (0.1% to 1%): Hypersensitivity reactions
• Frequency not reported: Anaphylactic reactions
• Postmarketing reports: Anaphylactic shock^[Ref]

Ocular

• Uncommon (0.1% to 1%): Testosterone (the active ingredient contained in FIRST-Testosterone) topical: Lacrimation increased
• Postmarketing reports: Testosterone topical: Intraocular pressure increased, vitreous detachment^[Ref]

Renal

• Postmarketing reports: Nephrolithiasis, renal colic, renal pain^[Ref]

See also:

Frequently asked questions

• Is Jatenzo cost covered by insurance?
• Is Xyosted a controlled substance?
• What are the brands of testosterone?

Further information

FIRST-Testosterone side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer