When two or more
medicines are taken together, it can change how the medicines work and increase the risk of side-effects. In medical terms, this is called as a
Drug Interaction.
Clarithromycin interacts with
theophylline, which is used for the treatment of respiratory disorders. The use of Clarithromycin and
theophylline together result in increased blood levels of theophylline. Theophylline levels in the blood should be monitored in the patients who are on treatment with high doses of theophylline.
There may be an interaction of
Clarithromycin with
terfenadine, which is used to treat allergic reactions. When
Clarithromycin is used in combination with terfenadine, the level of an active breakdown product of terfenadine was three times greater as compared to the case when terfenadine is given
alone. The use of Clarithromycin and terfenadine at the same time is not recommended.
Your doctor's guidelines may need to be followed while taking this medicine along with
omeprazole, which is used to treat acidity problems. When
Clarithromycin is used in combination with
omeprazole, the levels of
omeprazole in the blood are increased in comparison to when
omeprazole is given
alone.
Special instructions need to be followed while taking this medicine along with
verapamil, which is a
calcium channel blocker used in the treatment of heart problems. The use of
Clarithromycin and verapamil together results in symptoms such as low blood pressure, decreased heart rate, and accumulation of lactic acid which reduces the pH of blood excessively (lactic
acidosis). Caution is advised when verapamil and other
calcium channel blockers such as verapamil,
amlodipine,
diltiazem are given in combination with Clarithromycin.
Your doctor's guidelines may need to be followed while taking this medicine along with
digoxin, which is used to treat various heart problems. When
Clarithromycin is given in combination with
digoxin, inactivation of P-glycoprotein by Clarithromycin may result in an increased absorption of digoxin. It may also result in serious harmful effects in some patients irregular heartbeat that can be possibly fatal. Levels of digoxin in the blood should be monitored carefully, especially in the patients who have with digoxin level in the upper therapeutic range.
Special instructions need to be followed while taking this medicine along with oral
anticoagulants, which are used to prevent clotting of blood. Use of
Clarithromycin along with oral anticoagulants enhances the effect of anticoagulants. Patients taking Clarithromycin and anticoagulants should carefully monitor the time that blood takes to clot (prothrombin time).
Clarithromycin interacts with
ritonavir, which is a
protease inhibitor used in the treatment of HIV/AIDS. The use of Clarithromycin together with ritonavir results in an increased level of Clarithromycin in the blood and a decrease in the breakdown product of Clarithromycin. Patients who are on treatment with both the drugs require no adjustment of dosage in patients with the normal functioning of kidneys taking ritonavir. As the levels of the breakdown product of Clarithromycin are significantly decreased, treatment with other antibacterial therapy should be taken into consideration. The dose of Clarithromycin more than 1000 mg a day should not be given together with protease inhibitors.
There may be an interaction of
Clarithromycin with
fluconazole, which is used to treat fungal infections. When
Clarithromycin is given in combination with
fluconazole, the blood levels of Clarithromycin are increased. There is no need to adjust the dose when Clarithromycin is given together with fluconazole.
Clarithromycin may interact with
zidovudine, which is used to prevent and treat HIV/AIDS. When
Clarithromycin is used in combination with zidovudine, the blood levels of zidovudine are decreased in comparison to when zidovudine is given
alone. The use of both the drugs should be separated by a time interval of 2-4 hours.
Your doctor's guidelines may need to be followed while taking this medicine along with Triazolobenzodiazepines including
alprazolam,
midazolam, and
triazolam, which are used to treat
anxiety disorders. When an oral and intravenous dose of midazolam is given in combination with
Clarithromycin, 500 mg twice a day for 7 days, the exposure of the body to the drug (AUC) is increased. Also, the use of triazolam with Clarithromycin may result in the effects on the central nervous system including sleepiness and
confusion. When Clarithromycin is given in combination with an oral dose of midazolam, triazolam or alprazolam, adjustment of dose should be done cautiously and appropriately. The patient should be monitored for any increase in the medicinal effects on the central nervous system.
Special instructions need to be followed while taking this medicine along with
tolterodine, which is used in the treatment of involuntary leakage of urine. Blockage of the
enzyme CYP3A, which is responsible for the breakdown of tolterodine, results in a significantly greater amount of tolterodine in blood. When
Clarithromycin is given in combination with tolterodine, 1 mg of tolterodine twice a day is recommended in patients who are deficient in CYP2D6 activity.
Clarithromycin interacts with
sildenafil,
tadalafil, and
vardenafil, which are used in the treatment of erectile dysfunction. Clarithromycin
inactivates CYP3A
enzyme and the use of sildenafil,
tadalafil, and vardenafil together with Clarithromycin will result in increased absorption of sildenafil, tadalafil, and vardenafil. The use of Clarithromycin in combination with these drugs is not recommended.
There may be an interaction of
Clarithromycin with
efavirenz and
nevirapine, which are used to treat HIV/AIDS,
rifampicin,
rifabutin, and
rifapentine, which are used to treat bacterial infections. When
Clarithromycin is used in combination with these drugs, it will result in an increase in the breakdown of Clarithromycin, thus decreasing the amount of Clarithromycin in the blood. A different treatment with antibacterials should be initiated in patients who are on treatment with these drugs which are inducers of CYP3A.
Clarithromycin may interact with
colchicine, which is used to treat
gout characterized by severe
pain, redness, and tenderness in joints. When
Clarithromycin is given in combination with colchicine, the maximum amount of drug in the blood (Cmax) is increased as well as the exposure of the body to the drug (AUC) is increased to a greater extent. When Clarithromycin is prescribed in combination with colchicine to patients with normal functioning of kidneys and
liver, the dose of colchicine should be reduced. This combination should not be given to patients who have kidney or
liver problems.
This page does not contain all the possible interactions of Clarithromycin. Share a list of all medicines that you use with your doctor and pharmacist. Do not start, stop, or change the dose of any
medicines without the approval of your doctor.