Testosterone is administered through injections, topical gels, skin patches, oral capsules, nasal gel, or implanted pellets. The best option depends on how often you’re willing to dose, whether you’re comfortable with needles, and how steady you need your hormone levels to stay. Each method delivers the same hormone but differs in convenience, cost, and how your body absorbs it.
Injections
Injections are the most commonly prescribed form of testosterone therapy and come in two main styles: intramuscular (into the muscle) and subcutaneous (into the fat layer just beneath the skin). Both approaches use oil-based testosterone that absorbs slowly into the bloodstream over days to weeks.
For intramuscular injections, the most common sites are the gluteal muscles (buttocks) and the deltoid (upper arm). Blood flow varies between muscle groups, which slightly affects how fast the testosterone reaches your bloodstream. Subcutaneous injections typically go into the belly fat, about 3 to 5 centimeters to the side of the navel, or into the thigh. Subcutaneous shots use a smaller, thinner needle (usually a 23- to 25-gauge, 5/8-inch needle with a 1-mL syringe), which many people find less intimidating than the longer needles used for deep muscle injections.
The two most widely used injectable forms are testosterone cypionate and testosterone enanthate. These are considered short-acting, meaning they’re typically injected every one to two weeks. Many men learn to self-inject at home after an initial demonstration from their provider. Rotating between injection sites on alternating sides helps prevent scar tissue buildup.
A longer-acting injectable option, testosterone undecanoate, requires a much larger injection volume (3 to 4 mL compared to the typical fraction of a milliliter for other forms). Because of this volume, it’s injected slowly over two to three minutes and is usually administered in a clinic rather than at home. The trade-off is far less frequent dosing, with injections spaced weeks to months apart once levels stabilize.
Topical Gels and Patches
Testosterone gels are applied daily, usually to the upper arms, shoulders, or abdomen depending on the specific product. You squeeze out a measured dose from a pump or packet, rub it into your skin, and let it dry before putting on a shirt. Gels deliver a steady, low-level dose that absorbs through the skin throughout the day, which avoids the peaks and valleys that can come with injections.
The main concern with gels is accidental transfer. If another person, especially a child, touches the application area before it’s dry or before you’ve washed the site, they can absorb testosterone through their own skin. To prevent this, wash your hands thoroughly with soap and water after applying, cover the area with clothing once the gel has dried, and wash the application site before any skin-to-skin contact with others.
Transdermal patches work on a similar principle but are worn on the skin (often the back, abdomen, upper arm, or thigh) and replaced daily. Skin irritation at the patch site is a common complaint, which leads some people to prefer gels instead.
Oral Capsules
Oral testosterone capsules are a newer option that bypasses a problem that sidelined earlier oral formulations: liver toxicity. Older oral testosterone pills were processed directly by the liver and could cause damage over time. The current capsules use a form called testosterone undecanoate, which is a fat-soluble molecule. Instead of going straight to the liver, it gets absorbed through the intestinal lymphatic system, the same network your body uses to transport dietary fats. This detour significantly reduces liver strain.
The typical dose is taken twice daily, roughly 12 hours apart, and must be taken with food. Because the absorption depends on fat digestion, taking the capsules on an empty stomach dramatically reduces how much testosterone actually reaches your bloodstream. For people who want to avoid needles and skin products entirely, oral capsules offer a straightforward daily routine.
Nasal Gel
A nasal testosterone gel is applied inside the nostrils, typically three times per day. It absorbs through the nasal lining directly into the bloodstream. The frequent dosing schedule is the biggest drawback, but some people prefer it because it carries virtually no risk of skin-to-skin transfer and doesn’t involve injections. Each dose is a small pump applied just inside the nostril.
Subcutaneous Pellets
Testosterone pellets are small, rice-grain-sized implants placed under the skin during a brief in-office procedure. A provider makes a tiny incision, usually in the hip or buttock area, and inserts the pellets into the fat layer using a specialized tool. The whole process takes a few minutes under local anesthesia.
The appeal of pellets is their duration. A standard dose lasts about six months before re-implantation is needed, with patients in one large study returning for their next insertion at an average of 5.8 months. That means only two office visits per year for ongoing therapy. The main complication is pellet extrusion, where one or more pellets work their way back out through the incision site before fully dissolving. This happens in a small percentage of procedures and can shorten the effective duration, but multiple extrusions only occurred after about 3.6% of insertions in published data.
How Levels Are Monitored
Starting testosterone therapy isn’t a set-it-and-forget-it process. Your provider will check blood levels at specific intervals depending on which method you’re using. For gels, patches, and nasal formulations, an initial follow-up blood draw is typically done two to four weeks after starting. For injectable cypionate or enanthate, the recommendation is to wait until you’ve completed three to four injection cycles before testing, since it takes that long for levels to stabilize. For pellets, a first check at two to four weeks after implantation helps determine whether the dose needs adjusting, followed by another test at 10 to 12 weeks.
Once you’re on a stable dose, testosterone levels are rechecked every 6 to 12 months. Your provider will also monitor your red blood cell concentration (hematocrit) on the same schedule, since testosterone stimulates red blood cell production and levels above 54% can increase the risk of blood clots. For men over 55, prostate-specific antigen (PSA) testing may be discussed as part of routine screening.
When Effects Become Noticeable
One of the first questions people have after starting testosterone is how long it takes to feel different. The timeline varies by symptom. Improvements in libido, including sexual thoughts, desire, and morning erections, tend to appear within the first three weeks and plateau quickly. Self-confidence begins improving between three and six weeks. Depression scores drop noticeably by around six weeks, with overall mood continuing to improve through weeks six to nine. Concentration improvements show up as early as three weeks with some formulations, though others may take closer to nine weeks.
Changes in body composition, such as increased muscle mass and reduced body fat, take considerably longer and typically require months of consistent therapy combined with physical activity. If you don’t notice changes in the expected timeframe, that’s useful information for your provider to adjust the dose or switch delivery methods rather than a sign that therapy isn’t working.
Choosing a Method
The decision often comes down to lifestyle and personal preference more than medical superiority. Injections offer the lowest cost and flexible dosing but require comfort with needles. Gels provide stable daily levels but demand careful hygiene habits to protect household members. Oral capsules are convenient if you can remember twice-daily dosing with meals. Pellets require the least ongoing effort but involve a minor procedure twice a year. Nasal gel avoids most drawbacks of other methods but needs to be applied three times daily.
Your provider may also steer you toward one option based on how your body responds. Some people metabolize topical testosterone poorly through the skin and get better results with injections. Others experience uncomfortable peaks and troughs on injections and do better with a steady-state method like gels or pellets. It’s common to try more than one delivery method before settling on the right fit.