How long does Clindamycin take to start working? (3+ tips)

In this article, we will discuss the expected time frame for Clindamycin to show initial effects. Furthermore, we’ll explore the factors that may influence Clindamycin’s onset of action, potential side effects and precautions while using Clindamycin and tips for optimizing the effectiveness of Clindamycin. 

How long does Clindamycin take to start working?

The onset of action or the time Clindamycin takes to start work can vary. There is not a “one size fits all” timeframe for when it starts exerting its effects. Usually, it is considered that patients start feeling better 72 hours after starting the course but again it depends on dose and formulation among other factors. (2)

Clindamycin is an FDA-approved antibiotic that belongs to the lincosamide class. It exerts its effects by inhibiting the protein synthesis of bacteria that are essential for its growth and replication. In this way, it is used to treat a broad variety of bacterial infections including respiratory tract infections, bone and joint infections, UTIs and dental infections among others. (1)

It’s important to recognize that everyone is unique and react differently to medications. The time it takes for Clindamycin to start working can depend on specific factors like the type and severity of infection, the dosage strength administered and the frequency of dosing etc. (1)

In some cases, people may start to experience relief from symptoms within a few days of starting the medication, while in others it may take longer. If you have concerns about the effectiveness of Clindamycin or if your symptoms persist or worsen, contact your healthcare provider. (1)

What factors can influence the onset of action of Clindamycin? 

The onset of action of Clindamycin can be influenced by various factors including: (1)

Route of administration:

The route of administration can influence the rate at which the drug is absorbed and distributed throughout the body. As Clindamycin is available in both oral and IV forms, intravenous administration is considered to have a faster onset compared to oral administration. 


Different formulations of Clindamycin may have varying rates of absorption. For example, Clindamycin phosphate is a water-soluble form used for injection while Clindamycin hydrochloride is an oral form. The choice of formulations plays a crucial role in how quickly the drug becomes available for therapeutic action. 

Food intake: 

Clindamycin absorption can also be affected by food. Taking Clindamycin with food may help reduce gastric irritation but can also decrease the rate of absorption. So, for optimal absorption, Clindamycin is often recommended to be taken on an empty stomach. 

Gastrointestinal factors:

Your gastrointestinal conditions such as your gut health and the transit time can also influence the absorption of Clindamycin. Individuals who have certain gastrointestinal disorders may experience altered absorption rates, thus increasing the time for Clindamycin to exert its therapeutic effects. 

Liver function:

Clindamycin is typically metabolized or broken down by the liver. Any impairment in liver function may affect the metabolism and elimination of the drug, potentially influencing its onset of action. 

Kidney function:

While Clindamycin is not primarily excreted through the kidneys, renal function may play a significant role in drug elimination from the body. Any impairment in the kidney which may alter its functions may need dosage adjustment. 

Patient-specific factors:

The pharmacokinetics of Clindamycin are significantly influenced by individual patient characteristics such as age, weight and overall health. Pediatric and geriatric patients, for example, may metabolize and eliminate the drug differently. 

Microbial susceptibility:

The effectiveness of Clindamycin is also thought to be dependent on the susceptibility of target bacteria. The type of bacteria and the specific infection causing it can impact how quickly the drug exhibits its therapeutic effects. 

Concomitant use of medications:

If you’re taking other medications concurrently with the use of Clindamycin, the chances of drug-drug interactions are high which can potentially impact the absorption, distribution, metabolism and elimination of Clindamycin. 

What are the different formulations and dosage strengths of Clindamycin?

The onset of action of Clindamycin can vary depending on the formulation, route of administration and the specific condition being treated. Here are some formulations of Clindamycin and their onset of action: (1,2)


Route of administration

Dosage strengths

Typical onset of actions

Clindamycin capsules Oral 75mg, 150mg, 300mg 1-3 hours after ingestion
Clindamycin oral solution Oral 75mg/5ml

Variable – starts after ingestion

(Liquid form has a faster onset of action than capsules)

Clindamycin injection Intravenous and intramuscular (IV and IM) 150mg/ml, 300mg/ml

IV: Faster onset

IM: Delayed onset

Clindamycin phosphate injection Intravenous (IV) 150mg/ml, 300mg/ml Faster onset after entering the bloodstream
Clindamycin phosphate topical gel/ lotion Topical 1%, 2% Variable, localized action on the skin
Vaginal Clindamycin cream/suppositories Vaginal Cream: 2% Localized action in the vaginal area

What are the potential side effects of Clindamycin?

Some common side effects associated with Clindamycin use may include: (1)

Gastrointestinal distress

  • Nausea
  • Vomiting
  • Abdominal pain
  • Diarrhea

Skin reactions

  • Rashes
  • Itching
  • Hives

Pseudomembranous Colitis (inflammation of the colon)

Local reactions (for topical use)

  • Skin irritation
  • Dryness
  • Peeling

Serious side effects of Clindamycin which are less common: (1)

  • Allergic reactions – swelling of the face or tongue, difficulty breathing and redness, swelling, irritation on the skin.
  • Liver dysfunctions- jaundice, dark urine and persistent nausea. 
  • Blood disorders- changes in blood counts (leukopenia, neutropenia, thrombocytopenia)
  • Severe skin reactions- Steven Johnson syndrome, toxic epidermal necrolysis. 

What are the tips for faster Clindamycin response?

It’s crucial to maintain the safe and effective use of Clindamycin for best therapeutic outcomes at the intended times. You must ensure to follow the instructions provided by your healthcare provider like dosage regimen, frequency and timing of medication and the duration of the entire course. Take the full course even if the symptoms start to improve, otherwise, failure to do so might result in antibiotic resistance. (3)

Prefer taking Clindamycin on an empty stomach to enhance the rate of absorption but if you suffer gastrointestinal discomfort follow the advice of your doctor regarding food intake. 

Stay hydrated by drinking plenty of water as it may promote the absorption and distribution of the medication in the body. Also, avoid drinking too much alcohol during your antibiotic course as it may interact with Clindamycin and increase the risk of side effects. (1)

Tell your doctor about all the medications you might have been taking in the past or currently including prescribed, OTC and herbal supplements and also any known allergy or pre-existing health condition. This will help your doctor tailor the specific treatment plan and rule out the risks of interaction. 

Maintain a good hygiene, especially when using topical or vaginal Clindamycin formulations. Keep the affected areas clean and dry. Do not self-prescribe antibiotics or use leftover antibiotics from previous prescriptions as it may contribute to antibiotic resistance and may not be effective in treating the current infection. (2)

Be vigilant and keep an eye on how your body is reacting to the medication. If you experience any unusual system that persists and causes trouble, reach out to your doctor for dose adjustment or an alternative. 

Summing up Clindamycin’s onset of action discussion:

As a pharmacist, in my opinion, the onset of action of Clindamycin with liquid formulations is faster compared to solid dosage forms like capsules, however, its bioavailability and peak time of drug concentration is faster with the intravenous route of administration. Always follow the recommended guidelines prescribed by your healthcare provider and never choose the formulation or dose on your own.

Was this helpful?

Thanks for your feedback!