There is no clear statement on whether it is effective to stop taking tenofovir for three months and then take it again. Patients who stop taking tenofovir should closely monitor their DNA for several months before determining whether they need to continue taking the drug for treatment. Tenofovir should not be discontinued on its own, as this may result in deterioration of liver function or even life-threatening liver failure. If the patient stops taking the drug, liver function should be closely monitored by clinical or laboratory follow-up for at least several months to check for any recurrence of the disease before determining whether to resume treatment with the drug. Common adverse reactions to tenofovir such as new and worsening renal impairment are avoided with more nephrotoxic drugs. If the drug is overdosed, it should be monitored for signs of toxicity transfer, treatment should be given by a physician experienced in the management of chronic hepatitis B, and it is contraindicated for those who are allergic to excipients such as microcrystalline cellulose.